Air treatment system

ABSTRACT

An air treatment system having an improved control system. The control system may include a dynamic “dead front” display that varies the display based on mode of operation. The display may include capacitive touch sensors and include an array of capacitive film segments or traces integrated into the display. The control system may include a self-contained electronics module that can be tested and calibrated before installation in the ATS. A dust sensor assembly may be integrated into the electronics module. The front cover may be attached with a mechanical attachment at the top and a magnetic attachment on the bottom. The ATS may include a filter retainer assembly with a rotating clip configured to perform in a cam-like manner to firmly clamp the particulate filter and carbon filter in place.

BACKGROUND OF THE INVENTION

The present invention relates to air treatment systems and moreparticularly to a portable room air filtering system.

Air treatment systems continue to grow in popularity as concerns aboutair quality remain an issue of significant concern. This growth has ledto an increase in the use of commercial and residential air treatmentsystems. A conventional residential air treatment system is aself-contained unit that can be placed in a room where it is desirableto treat the air. Residential air treatment systems generally operate bydrawing room air into them, treating the air with one (or more)technologies, and releasing the treated air back into the room. Thetreated air contains a lower concentration of airborne contaminants thanin the room at large. The treated air mixes with the room air, and thus,the concentration of contaminants in the room air is reduced.

Air treatment systems are available with different types of controlsystems. The control systems provide different methodologies forcontrolling operation of the air treatment system and for allowingoperator input. The design and configuration of the control system canhave a significant impact on the function and aesthetic appeal of theair treatment system.

Many conventional air treatment systems include a series of specializedfilters that are tailored to address specific air quality issues. Forexample, residential air treatment systems often include a prefilter, aparticulate filter and an odor filter. The function of the prefilter istypically to remove relatively large elements from the air, such as hairand agglomerations of dust. A particulate filter typically functions toremove smaller airborne particles. Particulate filters are available ina variety of configurations. For example, a particulate filter mayinclude a pleated material with non-woven fibers that capture particlesand are effective as a HEPA filter. Odor filters are also available in avariety of types and configurations. Many odor filters include activatedcarbon that adsorbs a range of impurities, including without limitationmany organic chemicals. Conventional particulate filters and carbonfilters have a limited life and require occasional replacement. Thestructure of the air treatment system and the mechanisms used to securethe filters within the air treatment system can have a meaningful impactof the effectiveness of the system and can dramatically affect thecomplexity and amount of effort required to replace the filters.

There are other aspects that may have an impact on function andcommercial success of an air treatment system. For example, conveniencefeatures, such as power cord management, and mobility features, such asfeet and handles, can affect the user experience.

SUMMARY OF THE INVENTION

The present invention provides an air treatment system having animproved control system. In one embodiment, the control system includesa “dead front” display that provides the ATS with a clean and simpleappearance, and that facilitates an improved control experience. Thedisplay may include a plurality of informative display elements and aplurality of touch sensors that are selectively illuminated by anunderlying arrangement of light sources, such as LEDs. To produce thedesired graphics, each light source may be covered by a screen having amask layer and a diffuser layer. A translucent cover may be disposedover the control system to hide the underlying structure and allow thegraphic images to be seen only when illuminated. The translucent covermay be integrated into a removable front cover that closes the front ofthe ATS. In one embodiment, the electronics module includes a light ductassembly have a plurality of individual ducts joined side-by-side toshepherd light from the light sources to the corresponding displayelements.

In one embodiment, the touch sensors are capacitive sensors. In suchembodiments, a capacitive film, such as a transparent PET film coatedwith indium tin oxide, may be incorporated into the structure overlyingeach light source. For example, each light source may be covered by alaminated screen that includes a mask layer and a diffusing layer, andthe capacitive film may be implemented as an additional layer of thescreen. As another example, the capacitive film may be separate from thescreen and may be positioned above or below the screen where it iscapable of sensing the presence of an operator's finger. In analternative embodiment, conductive traces may be incorporated into thestructure overlying each light source to function as capacitive sensor.For example, a printed circuit board (“PCB”) may be positioned over alight duct array. The PCB may define openings over each individual lightduct and may include a trace around each opening that is associated witha light duct for an input display element. The PCB may also include arelatively large conductive trace that extends over a significantportion of the face of the PCB to provide a capacitive sensor that issensitive enough to function as a proximity sensor. The proximity sensormay be configured to sense the presence of an operator (e.g. anoperator's hand) within approximately two feet of the display.

In one embodiment, the ATS has a removable front cover that overlies thedisplay, and the control system is configured to recognize touchesdifferently depending on whether or not the cover is installed orremoved. This allows a user to control the system whether or not thecover is in place. In one embodiment, the control system is configuredto enable a different set of control options depending on whether or notthe cover is installed. For example, the control system may offer areduced set of control options and/or additional control options whenthe cover is removed. The control system may recognize whether the coveris installed or removed using one or more of the capacitive touchsensors, such as the proximity sensor.

In one embodiment, the control system includes a dust sensor that isintegrated into the electronics module. The dust sensor may be arrangedso that air is drawn into the dust sensor by virtue of the partialvacuum created by the ATS blower. After passing through the dust sensor,the air is passed through the filters and returned to the room in atreated state. Alternatively, the dust sensor may be arranged so thatair is drawn into the dust sensor by virtue of the flow of treated airdischarged by the ATS.

In another aspect, the present invention provides a front cover with amagnetic interlock that allows for easy installation and removal, aswell as allowing the control system to recognize whether or not thecover is installed. In one embodiment, the front cover includes one ormore mechanical attachment points at the top and one or more magneticattachment points at the bottom. The mechanical attachment point mayinclude a lip that is configured to catch on a corresponding structurein the ATS housing. For example, the lip may catch on the electronicsmodule to help ensure true registration between the front cover and theelectronics module. The size, shape and configuration of the catch mayvary. For example, it may extend generally across the width of the frontcover or it may extend across only a central portion of the front cover.As another example, the lip may be integrally formed with the frontcover or may be a separate component that is attached to the front coverafter manufacture. The front cover may be manufactured from atranslucent plastic that is configured to provide the appearance ofopacity, while allowing light from the display to shine through. In oneembodiment, the exposed surface of the front cover may be covered with afilm that is applied using an in-mold film process. In anotherembodiment, the exposed surface may be covered with a thin layer ofpaint using a spray process or a direct transfer process (i.e. silkscreen or pad printing, or thermal film transfer). Alternatively, thefront cover may be generally opaque and may include a window overlyingthe display. The window may be manufactured from a translucent plasticthat is configured to provide the appearance of opacity, while allowinglight from the display to shine through. In one embodiment, the exposedsurface of the window may be covered with a film that is applied usingan in-mold film process. In another embodiment, the exposed surface ofthe window may be covered with a thin layer of paint using a sprayprocess or a direct transfer process (i.e. silk screen or pad printing,or thermal film transfer).

In another aspect, the present invention provides an ATS housing withinterchangeable bases. The number and style of bases may vary, but inone embodiment the ATS may include a plurality of bases that providedifferent structure for receiving the electrical cord and/or differentfeet for supporting the ATS. With regard to the electrical cord, the ATSmay be capable of receiving a base with a structure for manuallywrapping an electrical cord or a retractable cord assembly with anautomatic take-up reel. With regard to the feet, the base may includefixed feet, casters, wheels and/or a single elongated roller. As analternative to interchangeable bases, the base may be integrated intothe ATS and may include feet and a single elongated roller. The ATS mayinclude a handle at the top rear of the housing. In one embodiment, thehandle may extend essentially the full width of the ATS, therebyallowing the ATS to be grabbed in the center by a single hand or grabbedtowards opposite sides by two hands.

In another aspect, the present invention provides a filter retainerassembly that provides for easy and secure installation of the filters.In this embodiment, the ATS includes a particular filter and anactivated carbon filter. The activated carbon filter is fitted into thefilter housing first and the particulate filter is fitted into thefilter housing over the carbon filter. The particulate filter is securedto the ATS housing at its periphery by one or more clips that interactwith corresponding structure in the ATS. The clip or clips may beconfigured to perform in a cam-like manner to firmly clamp theparticulate filter and carbon filter in place. The ATS may also includea prefilter that is snap-fitted onto the particulate filter. Theprefilter may include a coarse filter media that is supported by agrid-like prefilter retainer.

The present invention provides an ATS with an improved control system.The use of a self-contained electronic module allows testing andcalibrating of the electronics before installation and assembly of theATS. It also facilitates replacement of the electronic module, ifnecessary. For example, the use of an on-board dust sensor with integralducting eliminates the need to separately install a dust sensor and towire the dust sensor to the electronics module. The control systemincludes a “dead front” display with integral capacitive touch sensors.This allows a completely sealed electronics module with no moving partsproviding increased reliability. The use of a “dead front” display allowa dynamic display that varies from mode to mode—not only providingimproved aesthetics, but also simplifying the display to facilitate easyoperation from one mode to another. The use of LEDs with multiple coloror brightness options allows the display elements to be illuminated indifferent configurations depending on use. Wireless connectivity allowscontrol and data exchange with remote devices without requiring light ofsight or infrared transmissive plastic, such as smart phones andtablets, including data logging and monitoring of historical trends.RFID tags may provide improved tracking of filter life and productefficacy, and may allow filter life reset without operator intervention.The dust sensor may be used not only to control blower speed, but alsoto provide more accurate filter life calculations. In another aspect,the ATS includes a front panel that can be easily removed and installedwith one hand, without the need to deeply bend or kneel to reach theattachment points. By being at least partially translucent or having apartially translucent window, the front cover can cover the electronicsmodule to provide a “dead-front” display. Further, the side and centerinlets allow air to freely enter the ATS. In another aspect, theprovision of interchangeable bases allows the ATS to be easilycustomized for different applications and for customers with differentpreferences. This provides more flexibility and rapid changeover betweenmodels with different features. For example, the type of feet can bevaried and the type of cord management feature can be varied. The use ofa one-piece handle that extends roughly the width of the ATS providesvarious benefits. It allows an operator to manipulate the ATS with oneor two hands at multiple wrist/hand angles. It can also be formed toprovide structural reinforcement underneath a cantilevered feature ofthe ATS. In one embodiment, the base can include casters or a centralroller that allow the ATS to be easily moved with a single hand engagingthe center of the handle. In another aspect, the present inventionprovides a simple and effective clip arrangement for securing theparticulate filter to the ATS. By positioning the clip or clips towardthe top of the filter and the catch toward the bottom, the filter can besecuring or released without deep bending or kneeling. The clip or clipsmay provide an improved seal by automatically draws the filter intotighter engagement with the sealing surface as they are engaged. Theclip or clips also work in only one direction, thereby ensuring that thefilter is installed in the correct orientation.

These and other objects, advantages, and features of the invention willbe more fully understood and appreciated by reference to the descriptionof the current embodiment and the drawings.

Before the embodiments of the invention are explained in detail, it isto be understood that the invention is not limited to the details ofoperation or to the details of construction and the arrangement of thecomponents set forth in the following description or illustrated in thedrawings. The invention may be implemented in various other embodimentsand of being practiced or being carried out in alternative ways notexpressly disclosed herein. Also, it is to be understood that thephraseology and terminology used herein are for the purpose ofdescription and should not be regarded as limiting. The use of“including” and “comprising” and variations thereof is meant toencompass the items listed thereafter and equivalents thereof as well asadditional items and equivalents thereof. Further, enumeration may beused in the description of various embodiments. Unless otherwiseexpressly stated, the use of enumeration should not be construed aslimiting the invention to any specific order or number of components.Nor should the use of enumeration be construed as excluding from thescope of the invention any additional steps or components that might becombined with or into the enumerated steps or components. Any referenceto claim elements as “at least one of X, Y and Z” is meant to includeany one of X, Y or Z individually, and any combination of X, Y and Z,for example, X, Y, Z; X, Y; X, Z; and Y, Z.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a front perspective view of an ATS in accordance with anembodiment of the present invention.

FIG. 1B is a rear perspective view of the ATS.

FIG. 2 is an exploded perspective view of the ATS showing the frontcover and filters removed from the ATS.

FIG. 3 is a cross-sectional view of the ATS taken along line 3-3 of FIG.1.

FIG. 4 is a schematic representation of the electronics module.

FIG. 5 is a front view of the electronics module.

FIG. 6 is a perspective view of the electronics module with the coverremoved.

FIG. 7 is an exploded perspective view of the electronics module.

FIG. 8 is a perspective view of a portion of the ATS showing the “deadfront” display with no elements illuminated.

FIG. 9A is a front view of the display showing the outline of alldisplay elements.

FIG. 9B is a front view of the display showing all display elementsilluminated in the “on” state.

FIG. 10 is a perspective view of a portion of the ATS showing the “deadfront” display showing various elements illuminated in different states.

FIG. 11 is a front view of the display when powered off.

FIG. 12 is a front view of the display when in the night mode.

FIG. 13 is a schematic representation of a control scheme in accordancewith an embodiment of the present invention.

FIG. 14 is a schematic representation of an alternative control scheme.

FIG. 15 is a schematic representation of a second alternative controlscheme.

FIG. 16 is a front perspective view of the ATS showing the air inlets.

FIGS. 17A-B are illustrations showing alternative methods for removingthe front cover.

FIG. 18 is a rear perspective view of the front cover.

FIGS. 19A-B are sectional views showing the top attachment point betweenthe front cover and the ATS.

FIGS. 20A-B are sectional views showing a bottom attachment pointbetween the front cover and the ATS.

FIG. 21 is a partially exploded front perspective view showing the ATSand three interchangeable bases.

FIG. 22 is a partially exploded rear perspective view showing the ATSand three interchangeable bases.

FIG. 23 is a bottom perspective view showing a base with fixed feet.

FIG. 24 is a bottom perspective view showing a base with casters.

FIG. 25 is a bottom perspective view showing a base with fixed feet anda roller.

FIG. 26 is a perspective view of a handle and a portion of the ATSincluding the handle.

FIG. 27 is a perspective view of the ATS with the front cover andprefilter removed.

FIGS. 28A-D are various drawings showing various stages of removal ofthe particulate filter.

FIG. 29A is a perspective view of the particulate filter.

FIG. 29B is a side elevational view of the particulate filter.

FIGS. 30A-D are a series of drawings representing actuation of a filterlatch in accordance with an embodiment of the present invention.

FIGS. 31A-D are a series of drawings representing actuation of a filterlatch in accordance with an alternative embodiment.

FIGS. 32A-D are a series of drawings representing actuation of a filterlatch in accordance with a second alternative embodiment.

FIG. 33A is a front perspective view of an ATS in accordance with analternative embodiment of the present invention.

FIG. 33B is a rear perspective view of the alternative ATS.

FIG. 34 is an exploded perspective view of the alternative ATS showingthe front cover and filters removed.

FIG. 35 is a cross-sectional view of the alternative ATS taken alongline 35-35 of FIG. 33A.

FIG. 36 is a schematic representation of the electronics module of thealternative ATS.

FIG. 37 is a perspective view of the display assembly of the alternativeATS.

FIG. 38 is a partially exploded perspective view of the display assemblyof the alternative ATS.

FIG. 39 is an exploded perspective view of the electronics module.

FIG. 40 is a perspective view of the alternative ATS showing the “deadfront” display with no elements illuminated.

FIG. 41 is a perspective view of the alternative ATS showing the “deadfront” display with the outline of all display elements.

FIG. 42 is a top perspective view of the alternative ATS showing the“dead front” display with the outline of all display elements.

FIG. 43 is a schematic representation of a control scheme in accordancewith an alternative embodiment.

FIG. 44 is a front perspective view of the alternative ATS showing theair inlets.

FIGS. 45A-B are illustrations showing alternative methods for removingthe front cover of the alternative ATS.

FIG. 46A is a rear perspective view of the front cover.

FIG. 46B is an exploded perspective view of the front cover.

FIG. 47 is a partially sectional view of a bottom portion of thealternative ATS.

FIG. 48A is a perspective view of an attachment plate.

FIG. 48B is a top plan view of the attachment plate.

FIG. 49 is an exploded perspective view of a portion of the filterhousing and a portion of the top housing.

FIG. 50 is a perspective view of the ATS with the front cover andprefilter removed.

FIG. 51A is a perspective view of the particulate filter.

FIG. 51B is a front view of the particulate filter.

FIG. 51C is a side elevational view of the particulate filter.

FIG. 51D is a top plan view of the particulate filter.

FIGS. 52A-D are various drawings showing different stages of removal ofthe particulate filter.

FIGS. 53A-D are a series of drawings representing actuation of analternative filter latch.

DESCRIPTION OF THE CURRENT EMBODIMENT A. Overview

An air treatment system (“ATS”) in accordance with an embodiment of thepresent invention is shown in FIG. 1. The ATS 10 of the illustratedembodiment generally includes a prefilter 100, a particulate filter 102and an activated carbon filter 104. The ATS 10 also includes a blower 56for drawing air from the environment into the ATS 10, moving the airthrough the filters and returning the filtered air to the environment.

The ATS 10 of the illustrated embodiment includes a control system 12having an electronics module 14 that provides a “dead front” display 16.The display 16 of this embodiment includes a plurality of displayelements 18 that can be selectively illuminated by the control system 12to provide dynamic content. Some of the display elements 18 may includea touch sensor 20 that allows operator input. In this embodiment, theelectronics module 14 includes a plurality of light sources 22, such asLEDs, each being uniquely assigned to a display element 18. Each lightsource 22 may be covered by a screen 24 having a mask layer 26 and adiffuser layer 28. Each touch sensor 20 may also include a capacitivefilm 30 positioned over the light source 22. In this embodiment, the“dead front” appearance may be created by a translucent front cover 32that hides the underlying structure and allows the display elements 18to be seen only when illuminated.

In another aspect, the front cover 32 is secured to the ATS 10 housing34 using a combination of mechanical and magnetic attachment points. Themechanical attachment point of the illustrated embodiment includes a lip36 at the top of the front cover 32 and a pair of magnets 90 at thebottom of the front cover 32. The lip 36 is configured to catch oncorresponding structure in the ATS housing 110. In use, the combinationof mechanical and magnetic attachment points allows the front cover 32to be easily removed and installed by an operator in the standingposition.

In yet another aspect, the ATS 10 is capable of receiving one of aplurality of interchangeable bases 40. Different bases 40 may providedifferent structure for receiving the power cord 42 and/or differentstructure for supporting the ATS 10. In FIG. 10, the ATS 10 includes abase 40 having a bobbin 44 for manually winding the power cord 42 andfixed feet 46. Alternative bases 40′, 40″ may include a cord retractionassembly with an automatic take-up reel and/or wheels, casters or aroller (See e.g. FIG. 25). The ATS 10 may also include a one-piecehandle 48 that extends essentially the full width of the ATS 10 to allowthe ATS 10 to be grabbed in the center by a single hand or towardopposite sides by two hands. In one alternative embodiment, base 40″includes a cord retraction assembly 45″ and a single centrally-locatedroller 47″. With this alternative base, the ATS 10 can be tilted forwardonto the roller 47″ and rolled from one location to another using thehandle 48.

In another aspect, the ATS 10 include a filter retainer assembly 50 thatfacilitates quick and secure installation and removal of the filter(s).The filter retainer assembly 50 of the illustrated embodiment includes acatch 52 and a plurality of clips 54 that are disposed on theparticulate filter and that interact with structure on the ATS housing110 to secure the particulate filter in place in the filter housing 112.The clips 54 may function in a cam-like manner to draw the particulatefilter into the filter housing 112 to facilitate and air tight seal.

Directional terms, such as “vertical,” “horizontal,” “top,” “bottom,”“upper,” “lower,” “inner,” “inwardly,” “outer” and “outwardly,” are usedto assist in describing the invention based on the orientation of theembodiments shown in the illustrations. The use of directional termsshould not be interpreted to limit the invention to any specificorientation(s).

B. General Construction

As noted above, the present invention is described in the context of aroom air treatment system that performs its general function byoperating a blower 56 to move air through a series of filters 100, 102and 104. The air treatment system 10 of the illustrated embodiment isconfigured to treat the air with three stages of filtration. The firststage is a course screen prefilter 100, which is intended to removelarge contaminates, such as hairs, lint fibers and large agglomerationsof dust (e.g. “dust-bunnies”). The second stage of filtration is aparticulate filter 102. Although the particulate filter 102specifications may vary, the illustrated ATS 10 includes a pleated HEPAfilter media, which reduces airborne particles as small as 0.009microns. The third stage of filtration is an activated carbon filter 104that includes a bed of granular activated carbon chips that have beencoated with various catalysts, which adsorb and convert the molecularcontaminants, such as formaldehyde, dioxin, and ozone. The carbon filter104 may be manufactured in accordance with the teachings of U.S. Pat.No. 7,316,732 for AIR TREATMENT FILTER AND RELATED METHOD, which issuedon Jan. 8, 2008, to Taylor, Jr. et al., and which is incorporated hereinin its entirety.

In the illustrated embodiment, the various filters 100, 102 and 104 arefitted into a filter housing 112. The filter housing 112 generallyincludes a carbon filter seat and a particulate filter seat. The twoseats are generally rectangular voids configured to receive the carbonfilter and particulate filter, respectively. The carbon filter seat issomewhat smaller in height and width than the particulate filter seat.As result, the filter housing 112 is stepped having a shoulder 114surrounding the carbon filter seat. The carbon filter 104 is firstfitted into the filter housing 112. The external dimensions of thecarbon filter 104 are slightly smaller than the dimensions of theportion of the filter housing 112 intended to receive the carbon filter104. As a result, there is a relatively tight fit between the carbonfilter 104 and the filter housing 112, which tends to move air throughrather than around the carbon filter 104. The particulate filter 102 isnext fitted into the filter housing 112. As noted above, the filterhousing 112 is stepped and includes a shoulder 114 against which theparticulate filter 102 is installed. The particulate filter 102 mayinclude a face seal (not shown) that engages the shoulder 114 to providea leaktight seal between the particular filter 102 and the filterhousing 112. This forces all air moving through the ATS 10 to flowthrough rather than around the particulate filter 102. Finally, theprefilter 100 is fitted into the filter housing 112 outside theparticulate filter 102. In this embodiment, the prefilter 100 includes aframe 116 and a layer of filter media (not shown). The frame 116 isconfigured to snap directly on to the particulate filter 102. Forexample, the frame 116 may include fingers 117 that extend inwardly andare capable of engaging the particulate filter frame. Except to theextent described, the prefilter 100, particulate filter 102 and carbonfilter 104 are generally conventional and therefore will not bedescribed in detail. Although the illustrated embodiment includes athree-stage filter arrangement, the present invention may beincorporated into ATSs with different filtering/treatment arrangements.

In this embodiment, the ATS 10 includes untreated air inlets 106 a-c inthe front that allow air to enter the system and an air outlet 108 inthe rear to return treated air to the environment. The ATS 10 includes ablower 56 that is housed in the lower rear portion of the housing behindthe prefilter 100, particulate filter 102 and the carbon filter 104. Inoperation, the blower 56 operates to draw untreated air from theenvironment into the ATS 10 through the inlets 106 a-c, move the airsuccessively through the three filters 100, 102 and 104 to treat the airand then discharged the treated air through the outlet 108 to return itto the environment. The sizes, shapes and configurations of the inlet,outlet and internal flow path are designed, among other things, toprovide the ATS with a compact footprint while still providing quiet andefficient operation. The size, shape and configuration of the inlet,outlet and internal flow path may vary from application to applicationas desired.

The illustrated ATS 10 is merely exemplary and the size, shape andconfiguration of the ATS may vary from application to application.

C. Control System

As noted above, the present invention includes a control system 12 thatcontrols operation of the ATS 10 and provides a user interface fordisplaying information and receiving input from the operator. Theprimary function of the control system 12 is to control the speed atwhich the ATS 10 operates to treat air based on sensed parameters oroperator input, to track the usage of filters, to notify the operator ofthe mode, motor speed setting and filter life and to accept operatorcommands. In general, the control system 12 varies the rate at which airis filtered by adjusting the speed of the blower 56. More specifically,the control system 12 controls operation of the blower 56 based onautomated or manual control schemes as described in more detail below.The control subsystem 60 may be configured to slowly transition betweenblower speeds, as desired. For example, in the illustrated embodiment,blower speed control is achieved by varying the duty cycle of the powersupplied to the blower 56. To provide a slow transition between motorspeeds, the control subsystem 60 may transition from one speed toanother by slowly incrementing or decrementing the duty cycle to movefrom the current speed to the desired speed. The timing, number and sizeof steps may vary from application to application depending on thedesired effect.

In the illustrated embodiment, the user interface is implemented as a“dead front” display 16 that is located toward the top of the frontcover 32 and includes integrated touch sensors. In use, the display 16displays information and receives operator input relevant to operationand maintenance of the system. For example, the control system 12 of theillustrated embodiment displays the current environmental dust level andinformation regarding the remaining life of the various filters. It alsoprovides touch sensitive buttons that allow an operator to control thesystem. The “dead front” display 16 includes a plurality of displayelements 18 that are visible only when illuminated. The control system12 is configured to selectively illuminate the individual displayelements 18 to provide a dynamic display that varies to provideinformation and to present control options that are available at anygiven time. In the illustrated embodiment, the display 16 includesinformative display elements 18 a that are illuminated to provideinformation regarding the status of the ATS or a monitoredcharacteristic, such as environmental air quality and filter life, andinput display elements 18 b that incorporate a touch sensor to allow anoperator to provide input to the control system 12. In addition toallowing user input, input display elements 18 b may also provideinformation regarding the status of the ATS, such as mode of operationand blower speed.

In the illustrated embodiment, the control system 12 includes anelectronics module 14 that is self-contained in the sense that itincludes all of the electronic components of the ATS 10, except for thepower supply components that convert AC wall power to the DC powerrequired to operate the ATS 10. In this embodiment, the power supplycomponents (not shown) are located in the base 40 of the ATS housing110. Referring now to the schematic representation of FIG. 4, theelectronics module 14 generally includes a control subsystem 60, an LEDarray 62, a capacitive touch sensor array 64, a dust sensor assembly 66,an RFID subsystem 68 and a wireless communication subsystem 70. Thecontrol subsystem 60 includes control circuitry and firmware that isconfigured to operate the ATS 10 and to coordinate the collection ofdata from various other subsystems, including the capacitive touchsensor array 64, the dust sensor 66, the RFID subsystem 68 and thewireless communication subsystem 70. The various modes of operation ofthe system are described in more detail below. The control subsystem 60also includes non-volatile memory for storage of preprogrammedoperational default values as well as historical operational data, suchas the life of the filters 100, 102 and 104, time of use, counters andother variables that might be used in connection with operation of theATS 10.

The electronics module 14 of the illustrated embodiment is shown inFIGS. 5-7. As shown, the electronics module 14 includes a housing 148that contains the circuitry for the control subsystem 60, the RFIDsubsystem 68 and the wireless communication subsystem 70, as well as theLED array 62, the capacitive touch sensor array 64 and the dust sensorassembly 66. The housing 148 generally includes a base 150 and a cover152. As noted above, the LED array 62 is configured to provideillumination of the display elements 18. More specifically, one or moreLEDs 62 a are positioned behind each display element 18, includinginformative display elements 18 a and input display elements 18 b. TheLEDs 62 a can be selectively illuminated by the control subsystem 60when it is appropriate to show an informative display element 18 or tomake an input display element 18 b available for input. Each LED 62 amay include a single LED or multiple LEDs that provide variousillumination options. For example, each LED 62 a may include a pluralityof LEDs of different brightness to allow the brightness of the displayelement 18 to be varied. As another example, each LED 62 may includedifferent color LEDs that can be illuminated separately or incombination to create different color illumination. In one embodiment,each LED 62 includes a red LED, a green LED and a blue LED, which can beilluminated in different combinations and at different levels ofbrightness to provide illumination of essentially any desired color. Inanother example, each LED 62 a may include a plurality of LEDs ofdifferent brightness and different colors. Although the illustratedembodiment includes an LED array 62 to provide illumination to thedisplay 16, the LED array 62 may be replaced or supplemented with othertypes of light sources, such as OLED, laser and EL light sources.

In the illustrated embodiment, the display 16 is a “dead front” displayin which non-illuminated display elements 18 are not visible. In thisembodiment, the region in which the display 16 is situated appears to bea simple continuation of the ATS housing 110 and, when no displayelements 16 are illuminated, the ATS 10 appears to have no userinterface. To produce the desired graphic elements, each display element16 includes a screen 74 that masks and diffuses the light produced bythe underlying LED 62. In the illustrated embodiment, the display 16includes two screens 74 a and 74 b, each covering a plurality of LEDsand providing masking and diffusing functions for a plurality of displayelements 18. Screen 74 a provides is associated with informative displayelements 18 a that provide information relating to the life of thevarious filters 100, 102 and 104. Screen 74 b is associated withinformative display elements 18 a that provide information relating toenvironmental air quality (e.g. based on dust sensor readings) and inputdisplay elements 18 b associated with power, mode and blower speedinputs. In the illustrated embodiment, each screen 74 is a laminatedstructure generally includes a diffusing layer and a masking layer. Thediffusing layer may be essentially any material capable of diffusinglight produced by the LEDs. For example, the diffusing layer may includea transparent substrate that is covered with a translucent film or othertranslucent coating. Alternatively, the diffusing layer may be atransparent material having a “roughed” or otherwise textured surface.In another alternative, the diffusing layer may be a sheet oftranslucent material. The masking layer may be essentially any materialcapable of masking the light to create the desired graphic, includingvarious opaque and translucent materials, such as inks, paints, films,and other adhesive layers. For example, the masking layer may be a layerof opaque film that defines an opening(s) in the shape of the desiredgraphic. It may also include combinations of different materials thatprovide different visual appearances. For example, the masking layer mayinclude an opaque region where no light transmission is desired, a firsttranslucent material where a background light transmission is desiredand a second translucent material where a foreground light transmissionis desired. The first and second translucent materials may produceregions that appear different through the use of different colortranslucent materials or translucent materials with different level oftransparency. The masking layer may be applied to the diffusing layer byprinting, thermal bonding, adhesive or other suitable means. In theillustrated embodiment, the masking layer is disposed on the outersurface of the diffusing layer opposite the LEDs or other light source,but it may be located elsewhere, if desired. Although the diffusinglayer and masking layer are part of a single laminated construction inthe illustrated embodiment, they may alternatively be separatecomponents. For example, they may be separately manufactured andpositioned adjacent to one another during assembly of the display 16.

In the illustrated embodiment, the light duct array 72 has a pluralityof individual ducts 72 a joined side-by-side to contain and guide lightfrom the light sources to the corresponding display elements. Each lightduct 72 a surrounds the light source and provides a reflective duct thatconveys the light from the light source 62 a to the appropriate portionof the screen 74 a, 74 b. For example, as shown in FIG. 3, one end ofeach light duct 72 a may be configured to be closely fitted over the LED62 a and the other end may engage the screen 74 b and be sized and shapeto follow the periphery of the associated display element 18. Theinternal surface of each light duct 72 a may be reflective, diffuse orhave other optical properties that are selected to provide thecorresponding display element 18 with the desired visual appearance. Inthe illustrated embodiment, the electronics module 14 includes two lightduct arrays 72—one for the filter life displays and the other for theremaining display elements. In this embodiment, each light duct array 72is manufactured as a single, integral unit, thereby facilitatingmanufacture and assembly of the electronics module 14. For example, eachlight duct array 72 may be injection molded and the internal surfacesmay be coated with a reflective or diffusive material depending on thedesired appearance.

As noted above, some of the display elements 18 are input displayelements 18 b that function as touch sensors to allow an operator toprovide input to the control subsystem 60. The input display elements 18b may be implemented using essentially any touch sensor technology thatcan be incorporated into the “dead front” display. In the illustratedembodiment, the input display elements 18 b are capacitive touchsensors. In this embodiment, the display 16 includes a capacitive touchsensor array 64 that includes a plurality of separate segments ofcapacitive film 64. Each segment of film is associated with a singletouch sensor. For example, each segment of film may be coextensive withthe display element 18 b associated with that touch sensor. Thecapacitive film 64 may be integrated into the screen 74 a, 74 b, forexample, as a separate layer laminated to diffusing layer 76 and/ormasking layer 78. Alternatively, the capacitive film 64 may be separatefrom the screen 74 a, 74 b. In the illustrated embodiment, each segmentof capacitive film 64 includes a tab 65 or other feature for connectingto the electronic module 14, and the underlying substrate 67 provides acommon grounding plane. The monitoring, control and operation of thecapacitive touch sensors may be generally conventional and thereforewill not be described in detail. Suffice it to say that the controlsubsystem 60 may recognize touches by sequentially taking readings fromthe separate segments of capacitive film and determining that a touchhas occurred when those current readings match predetermined values thatare typical of a touch.

As noted above, the electronics module 14 of the illustrated embodimentincludes a dust sensor assembly 66 that allows the control system 12 todetermine the level of air borne contaminants. In this embodiment thedust sensor assembly 66 includes a dust sensor 80, a sensor inlet 82, asensor duct 84, a sensor outlet 86 and a pair of sensor gaskets 88. Inthis embodiment, the dust sensor assembly 66 utilizes the partial vacuumcreated by the blower 56 to draw environmental air through the dustsensor 80. After passing through the sensor 80, the air is treated andreturned to the environment. As shown, the sensor outlet 86 is incommunication with the air flow path through the ATS 10 and ispositioned upstream from the filters 100, 102 and 104. The sensor 80 ismounted to the electronics module 14 in proper alignment with the sensoroutlet 86. The sensor inlet 82 is disposed in the cover 152 of theelectronics module 14 to provide a passage for environmental air toenter the sensor duct 84. The sensor inlet 82 may include filtermaterial (not shown) selected to prevent large particles, such as hair,lint and agglomerations of dust, from fouling the dust sensor 80. Thefilter material may be replaceable or cleanable. The sensor duct 84 isdisposed between the sensor 80 and the sensor inlet 82 to provide a flowpath to the sensor 80. Sensor gaskets 88 are positioned between the dustsensor 80 and the sensor outlet 86, and between the dust sensor 80 andthe sensor duct 84. In operation, the blower 56 draws air from theenvironment sequentially through the sensor inlet 82, the sensor duct84, the dust sensor 80 and the sensor outlet 86. As the air passesthrough the dust sensor 80, the level of dust in the air is measuredusing known techniques and apparatus.

Although not shown, the ATS 10 may also include a sensor that is capableof providing readings that are indicative of the presence or absence ofthe front cover 32. For example, in the illustrated embodiment, the ATS10 includes a hall-effect sensor that is positioned toward the bottom ofthe ATS 10 near one of the magnetic attachment points. When the frontcover 32 is removed, the absence of the magnets will change the readingsprovided by the hall-effect sensor. Alternatively, a separate interlockmagnet (not shown) may be incorporated into the front cover 32 is alocation near the electronics module 14 so that a hall-effect sensor,reed switch or other magnetic field sensor installed on the electronicsmodule 14 can be used to determine the presence or absence of the frontcover 32. Information about the status of the front cover 32 can be usedby the control subsystem 60 to affect operation of the system. Forexample, in one embodiment, the control subsystem 60 may automaticallyshut-off the blower 56 or otherwise change function when the front cover32 is removed. As another example, when the front cover 32 is removed,the control subsystem 60 may change the parameters used in determiningwhether a touch has occurred. This will allow the touch sensors to workequally well with and without the front cover 32 in place. As a furtherexample, the control subsystem 60 may enter into an alternative mode ofoperation when the front cover 32 is removed. This may result in thecontrol subsystem 60 changing the display elements 18, including theavailable input display elements 18 b.

The control system 12 may also include an RFID subsystem 68 that isconfigured to work with corresponding RFID tags in the replaceablefilters in the ATS 10 (e.g. particulate filter 102 and/or the activatedcarbon filter 104). The RFID subsystem 68 is generally conventional andtherefore will not be described in detail. Suffice it to say that withthe RFID subsystem 68, the control subsystem 60 can collect, accumulateand otherwise store filter life, time of use, elapsed time sinceinstallation, total affective consumption (e.g. motor speed multipliedby time of use), and other data in the RFID tags. When a filter isinstalled, the RFID reader/writer can read any data already stored inthe RFID tag, such as filter life, total amount of time filter has beeninstalled in any system, and total affective consumption of filter life.In this way, the system is able to provide proper tracking even when afilter is moved from one ATS to another. The RFID tags embedded in thefilter may also include a serial number that can be used to ensureauthenticity of the filter. For example, the control system 12 may storea table of valid serial numbers against which to compare the serialnumber or, if it has network capability, have the ability to compare aserial number against a table of valid numbers stored on the internet.Filter usage information may be used to provide a display of remainingfilter life and to provide prompts when filter replacement is required.The RFID subsystem 68 may also be used to determine when a filter hasbeen removed. This information may be useful in controlling ormaintaining statistics relating to use of the ATS 10. For example, thecontrol subsystem 60 may be configured to shut-off the blower when theparticulate filter 102 and/or the carbon filter 104 are removed. Asanother example, the control subsystem 60 may enter into a service modewhen one or both of the filters are removed. When in the service mode,the control subsystem 60 display information technical informationand/or provide control options that are specific to that mode. To helpensure proper alignment between the RFID reader/writer in the ATS 10 andthe RFID tag in the carbon filter 104, the carbon filter 104 and filterhousing 112 may be keyed so that the carbon filter 104 can only beinstalled in an orientation that provides alignment. For example, thebottom of the particulate filter 104 may include a keyway (not shown)and the filter housing 112 may include a corresponding key (not shown).When the RFID reader/writer is centrally located in a left/rightdirection the key may be centrally located because it will not matterwhich filter surface faces inwardly. When the RFID reader/writer is notcentrally located, it may be beneficial to provide a nonsymmetrical keyarrangement to ensure the desired filter surface faces inwardly.

As noted above, the control system 12 may include a wirelesscommunication subsystem 70 that allows the control subsystem towirelessly communication with other electronic devices, such as smartphones, tablets, personal computers, local wireless routers, broadbandwireless routers and other communication devices. In the illustratedembodiment, the wireless communication subsystem 70 allows the ATS 10 toexchange information with and receive commands from a remote device,such as a smart phone or tablet device running a dedicated application.For example, an application may be provided that allows an operator toenter ATS commands on an electronic device that are wirelesslycommunicated to and carried out by the control subsystem 60. As anotherexample, information collected by the ATS 10 can be communicated to theelectronic device for display within the application. With theillustrated embodiment, this may include filter life information foreach of the filters, mode of operation information, motor speedinformation and environmental air quality information derived using thedust sensor. The wireless communication subsystem 70 may utilizeessentially any wireless communication technology and protocol. Forexample, in the illustrated embodiment, the wireless communicationsubsystem 70 may have Bluetooth and/or WiFi capabilities.

The control system 12 may be configured to implement a wide variety ofcontrol schemes. In each case, the control system 12 may be configuredto provide a dynamic display 16 in which display elements 18 areilluminated and touch sensors are enabled based on changing variables,such as mode of operation and the values of monitored parameters. In theillustrated embodiment, the control system 12 implements a controlscheme having four general modes of operation, including a “smart” mode(or automatic mode) in which control is automated based at least in parton dust sensor readings, a “manual” mode in which the operator controlsthe blower speed, a “turbo” mode in which the blower 56 is temporarilyoperated at a high speed and a “night” mode in which the display 16 isoperated differently to limit night-time illumination. In connectionwith this control scheme, the display 16 is capable of displaying avariety of informative display elements 18 a and input display elements18 b (See FIGS. 5 and 9A). In the illustrated embodiment, each displayelement 18 includes two LEDs of different colors and/or differentintensity. One of the two LEDs is used to illuminate the display elementin a “present” state (e.g. a dimmer LED or a first color, such as asofter color). This state of illumination is used to make the displayelement 18 visible on the display 16, while providing a visualindication that it has not been selected or is not active. The other LEDis used to illuminate the display element in the “on” state (e.g. abrighter LED or a second color, such as a more vivid color). The “on”state is used to indicate that the display element is “on” or “active.”The number, type, arrangement, configuration and operation of thedisplay elements 18 may vary from application to application dependingin large part on the control scheme being implemented by the controlsystem 12.

In the illustrated embodiment, the informative display elements 18 ainclude an informative display element 200 that represents prefilterlife, a set of informative display elements 202 that representparticular filter life, a set of informative display elements 204 thatrepresent carbon filter life and a set of informative display elements206 that represent environmental dust level (See FIG. 9B). The inputdisplay elements 18 b generally include a power input display element208, a “smart” mode input display element 210, a “turbo” mode inputdisplay element 212, a “night” mode input display element 214 and aplurality of blower speed input display elements 216 (See FIG. 9B).

In the illustrated embodiment, the various filter life displays 200, 202and 204 are positioned between icon representations of the front cover32 and the ATS housing 110 (See FIG. 9B). These icons may be helpful inidentifying which filter life display is associated with which filter.In the illustrated embodiment, the front cover and ATS housing icons arestatically illuminated by a white LED operated at 50% brightness.

In the illustrated embodiment, the filter life display 200 for theprefilter includes an informative display element 200 can be illuminatedin the “present” state when the prefilter does not require maintenanceand in the “on” state when the prefilter requires maintenance (such ascleaning or replacement). The “present” state may be created bystatically illuminating a green LED. The “on” state may be provided byflashing a red LED.

In the illustrated embodiment, the filter life display 202 for theparticulate filter 102 includes four informative display elements 18 a,each representing a quarter of the filter lifer. When the filter lifedisplay is on, all four display elements 18 a are illuminated. Thenumber of elements 18 a illuminated in the “on” state representsremaining filter life. The remaining elements 18 a are illuminated inthe “present” state to provide a visual reminder that filter life isrepresented by quarters. The number of segments may vary fromapplication to application as desired. For example, additionalgranularity may be provided by increasing the number of informativedisplay elements 18 a associated with the filter life display 202. Inthe illustrated embodiment, the filter life display 202 for theparticulate filter incorporates color LEDs to assist in representingfilter life as follows:

75-100% life—all four segments illuminated green at 100% brightness

50-75% life—bottom three segments green at 100% brightness, top segmentwhite at 50% brightness

25-50% life—bottom segment amber at 100% brightness, top three segmentswhite at 50% brightness

1-10% life—bottom segment red at 100% brightness, top three segmentswhite at 50% brightness

0% life—bottom segment flashing red at 100% brightness, top threesegments white at 50% brightness

In the illustrated embodiment, the filter life display 204 for thecarbon filter 104 is essentially identical to the filter life display202 for the particulate filter 102 including four display elements 18 athat may be illuminated in “present” or “on” states using the samemethodology described above.

In the illustrated embodiment, the dust level display 206 includes aplurality of separate informative display elements 18 a that can beilluminated in “present” or “on” states. When the dust level display 206is being displayed, the number of informative display elements 18 a thatare illuminated in the “on” state represents the measured dust level andthe other informative display elements 18 a are illuminated in the“present” state. This allows the operator to better understand the dustlevel by comparing the ratio of “on” segments to total number ofsegments. In the illustrated embodiment, the dust level segments aregrouped into sets of three with a single set of LEDs being associatedwith each set of three segments. As a result, the dust level display 206of the illustrated embodiment has 15 segments, but only six differentsettings (i.e. 0 segments, 3 segments, 6 segments, 9 segments, 12segments or 15 segments). In the illustrated embodiment, the dust leveldisplay 206 incorporates color LEDs to assist in recognizing as follows:

-   -   Level 1—first segment illuminated green at 100% brightness,        remaining segments white at 50% brightness    -   Level 2—first two segments illuminated amber at 100% brightness,        remaining segments white at 50% brightness    -   Level 3—first three segments illuminated amber at 100%        brightness, remaining segments white at 50% brightness    -   Level 4—first four segments illuminated red at 100% brightness,        remaining segment white at 50% brightness    -   Level 5—all five segments illuminated red at 100% brightness

In this embodiment, the blower speed display element 18 b perform thedual function of displaying the current blower speed and receiving touchsensor input to allow the operator to manually set blower speed. As withthe dust level display, the blower speed display includes a plurality ofseparate display elements 18 that have two LEDs that can be selectivelyilluminated to represent a “present” state or an “on” state. Unlike thedust level display, the blower speed display is also a touch sensorarray that can be used by the operator to manually select a blowerspeed. When the blower speed is displayed, the number of blower speedinput display elements that are illuminated in the “on” state isselected to represent the blower speed and the other blower speed inputdisplay elements are illuminated in the “present” state so that theoperator can see the available blower speed options and compare theratio of “on” segments to “present” segments to understand the currentblower speed. In the illustrated embodiment, the “present” state may becreated by statically illuminating a white LED at 50% brightness. The“on” state may be provided by statically illuminated a blue LED at 100%brightness. To provide touch sensors, each blower speed display element18 b includes an associate segment of capacitive film. As noted above,the control subsystem 60 monitors the capacitive film segments todetermine when a touch has taken place. When a touch occurs, the controlsubsystem 60 may adjust the blower speed to match the selected setting.

In the illustrated embodiment, the power input display element 208 isilluminated red at 100% brightness when in the “present” state andilluminated white at 100% brightness when in the “on” state. The “smart”mode input display element 210 is illuminated white at 50% brightnesswhen in the “present” state and illuminated blue at 100% brightness whenin the “on” state. The “turbo” mode input display element 212 isilluminated white at 50% brightness when in the “present” state andilluminated blue at 100% brightness when in the “on” state. The “night”mode input display element 214 is illuminated white at 50% brightnesswhen in the “present” state and illuminated red at 50% brightness whenin the “on” state.

As noted above, the control system 12 of the illustrated embodimentimplements a control scheme with four different modes of operation:“smart” mode (or automatic mode), “manual” mode, “turbo” mode and“night” mode. This control scheme will be described with reference toFIG. 13. During the “smart” mode of operation, the control subsystem 60evaluates the dust sensor readings and determines a blower speed basedon those readings. This allows the ATS 10 to adapt to changing levels ofair borne dust in the environment. In this mode, the operator has theoptions of entering turbo mode, night mode, manual mode or powering offthe ATS. As such, the turbo mode input display element, the night modeinput display element, the various blower-speed input display elementsand the power input display element are illuminated. The turbo modeinput display element and the night mode input display element areilluminated in the “present” state. The smart mode input display elementand the power input display element are illuminated in the “on” state.If the smart mode input display element is touched when the system isalready operating in smart mode, the system will transition to themanual mode of operation. The blower speed input display elements areilluminated to show the current blower speed and available manualadjustment options in accordance with illumination methodology set forthabove. Additionally, in the smart mode, the dust level informativedisplay elements are illuminated to show the real-time dust level inaccordance with the illumination methodology set forth above. In thesmart mode, the filter life displays are illuminated for a specificperiod of time each time that user interacts with the ATS 10. Forexample, the control subsystem 60 may illuminated the filter lifedisplays for a period of 15 seconds each time that an operator interactswith a touch sensor in the display 16. Additionally, the filter lifedisplays may be illuminated whenever and for so long as a filter needsattention (e.g. any one of the filters needs to be cleaned or replaced).

The control subsystem enters the manual mode (or direct mode) when theoperator touches a blower speed input display element 18 b. Once in themanual mode, the control subsystem 60 operates the blower 56 at thespeed selected by the operator. In this mode, the operator has theoptions of entering turbo mode, night mode, smart mode, adjusting blowerspeed or powering off the ATS. As such, the turbo mode input displayelement, the night mode input display element, the smart mode inputdisplay element, the various blower-speed input display elements and thepower input display element are illuminated. The smart mode inputdisplay element, turbo mode input display element and night mode inputdisplay element are illuminated in the “present” state. The power inputdisplay element is illuminated in the “on” state. The blower speed inputdisplay elements are illuminated to show the current blower speed andavailable manual adjustment options in accordance with illuminationmethodology set forth above. Additionally, the dust level informativedisplay elements are illuminated to show the real-time dust level inaccordance with the illumination methodology set forth above. In thismode, the filter life displays are illuminated for a specific period oftime each time that user interacts with the ATS 10. For example, thecontrol subsystem 60 may illuminated the filter life displays for aperiod of 15 seconds each time that an operator interacts with a touchsensor in the display 16. Additionally, the filter life displays may beilluminated whenever and for so long as a filter needs attention (e.g.any one of the filters needs to be cleaned or replaced).

The turbo mode is entered when the operator touches the turbo mode inputdisplay element. Once in the turbo mode, the control subsystem 60operates the blower 56 at the highest speed setting (or some otherpredetermined speed setting) for a preset period of time (e.g. 30minutes) and then returns automatically to the previous mode ofoperation. The turbo mode may be interrupted by a button touch, in whichcase the system may transition out of the turbo mode prior to expirationof preset period of time. In this mode, the operator has the options oftouching the smart mode input display element to enter smart mode,touching a blower speed input display element to adjust blower speed andenter the manual mode or touching the power input display element topower off the ATS. Further, the operator has the option of touching theturbo mode input display element to cause the system to immediatelyreturn to the previous setting. As such, the turbo mode input displayelement, the smart mode input display element, the various blower-speedinput display elements and the power input display element areilluminated. The turbo mode input display element and power inputdisplay element are illuminated in the “on” state while the smart modeinput display element is illuminated in the “present” state. The blowerspeed input display elements are illuminated to show the current blowerspeed and available manual adjustment options in accordance withillumination methodology set forth above. Additionally, the dust levelinformative display elements are illuminated to show the real-time dustlevel in accordance with the illumination methodology set forth above.In this mode, the filter life displays are illuminated for a specificperiod of time each time that user interacts with the ATS 10. Forexample, the control subsystem 60 may illuminated the filter lifedisplays for a period of 15 seconds each time that an operator interactswith a touch sensor in the display 16. Additionally, the filter lifedisplays may be illuminated whenever and for so long as a filter needsattention.

The night mode is entered when the operator touches the night mode inputdisplay element. Once in the night mode, the control subsystem 60continues to operate the ATS 10 in the same mode, but the content of thedisplay is reduced to minimize light emissions. In this mode, theoperator has the options of disabling night mode (i.e. re-enabling thedisplay in accordance with the current mode of operation) by touch thenight mode input display element or powering off the ATS by touching thepower input display element. In the night mode, only the night modeinput display element and power input display element are illuminated,and they are both illuminated in the “on” state. In an alternativeembodiment, the control subsystem 60 may be configured to re-enable thedisplay 16 (in whole or in part) when the operator comes within closeproximity to the display 16. For example, control subsystem 60 may usethe capacitive touch sensor array 64 to sense proximity of the operatorand use that as a trigger to illuminate all of the input displayelements 18 b so that the operator has a full set of controls. If theoperator does not enter a command within a specific period of time (e.g.15 seconds) after the display 16 has been re-enabled, the controlsubsystem 60 may return to the display 16 to the night mode.

When the ATS 10 is plugged in, but not powered on, the control subsystem60 illuminate the power input display element in the “present” state.This allows the operator to see the power control element. Once thepower button is touched, the control subsystem 60 may start the systemin smart mode or in manual mode. When started in smart mode, the controlsubsystem 60 takes dust sensor readings, determines the appropriateblower speed based on the dust sensor readings and then engages theblower at the determined speed. All of these steps are takenautomatically without the need for operator input. When started inmanual mode, the control subsystem 60 does not start the blower 56 untildirected to do so by operator input, for example, by the operator touchone of the blower speed input display elements 18 b.

The control scheme described above is merely exemplary. The controlsystem 12 may implement a variety of alternative control schemes. Forexample, one alternative control scheme is shown in FIG. 14. Thisalternative control scheme is essentially identical to the controlscheme discussed above, except as described here. To implement thiscontrol scheme, the display may include an additional mode controlbutton associated with the “manual” mode (labelled “user” in FIG. 14).With this control scheme, the operator is required to use the modecontrol buttons to transition between different modes of operation. Forexample, the operator is required to touch the “user” mode input displayelement to enter the manual mode of operation (rather than simplytouching a blower speed input display element). Once in manual mode, theoperator can control the blower speed by touching the desired blowerspeed input display element. As another example of this control scheme,the operator can only leave the turbo mode by touching the turbo modeinput display element or allowing the preset time to pass. Similarly,the operator can only leave the night mode by touching the night modeinput display element.

Another alternative control scheme is shown in FIG. 15. In thisembodiment, the control scheme is essentially identical to the firstcontrol scheme discussed above, except as described here. To implementthis control scheme, the display includes an additional mode controlbutton associated with the “options” mode (labelled “options” in FIG.15). When the system is powered on, it starts in the “smart” mode andthe blower speed is set automatically based on input from the dustsensor. To provide additional control options, the “options” mode buttonmust be touched. In the “smart” mode, the power input display element isilluminated in the “on” state, the smart mode input display element isilluminated in the “on” state, the options mode input display element isilluminated in the “present” state and the dust level display isilluminated. The turbo mode input display element, the night mode inputdisplay element and the blower speed display are off. In the smart mode,the operator can touch the power input display element to power off thesystem or touch the options mode input display element to transitioninto the options mode.

Once in the “options” mode, the power input display element isilluminated in the “on” state, the smart mode input display element isilluminated in the “on” state, the options mode input display element isilluminated in the “on” state, the dust level display is illuminated andthe blower speed display is illuminated. Additionally, the turbo modeinput display element and the night mode input display element areilluminated in the “present” state. In the options mode, the operatorcan touch the power input display element to power off the system, touchthe smart mode input display element to return to the smart mode, touchthe options mode input display element to return to the smart mode,touch the turbo mode input display element to enter turbo mode, touchthe night mode input display element to enter night mode or touch ablower speed input display element to select a blower speed and entermanual mode. If no button is touched within a specified period of time(e.g. 60 seconds), the system may automatically revert to the smartmode.

Once in the “manual” mode, the power input display element isilluminated in the “on” state, the options mode input display element isilluminated in the “present” state, the dust level display isilluminated and the blower speed display is illuminated. Additionally,the smart mode input display element, the turbo mode input displayelement and the night mode input display element are off. In the manualmode, the operator can touch the power input display element to poweroff the system, touch the options mode input display element to enter a“manual options” mode or touch a blower speed input display element toselect a blower speed. While the system remains in manual mode, it willcontinue to operate the blower at the speed selected by the operator.

Once in the “manual options” mode, the power input display element andthe options mode input display element are illuminated in the “on”state, and the dust level display and blower speed display areilluminated. Additionally, the smart mode input display element, theturbo mode input display element and the night mode input displayelement are illuminated in the “present” state. In the manual optionsmode, the operator can touch the power input display element to poweroff the system, touch the smart mode input display element to return tothe smart mode, touch the options mode input display element to returnto the manual mode, touch the turbo mode input display element to enterturbo mode, touch the night mode input display element to enter nightmode or touch a blower speed input display element to select a blowerspeed and return to the manual mode. If no button is touched within aspecified period of time (e.g. 60 seconds), the system may automaticallyrevert to the smart mode. If no button is touched within a specifiedperiod of time (e.g. 60 seconds), the system may automatically revert tothe manual mode.

Once in the “turbo” mode, the control subsystem operates the blower atthe highest speed setting (or some other predetermined speed setting)for a preset period of time (e.g. 30 minutes) and then returnsautomatically to the previous mode of operation. The turbo mode may alsobe interrupted by a button touch, in which case the system maytransition out of the turbo mode prior to expiration of preset period oftime. The turbo mode input display element and power input displayelement are illuminated in the “on” state. The blower speed display anddust level display are also illuminated. Additionally, the smart modeinput display element, the options mode input display element and thenight mode input display element are off. In this mode, the operator hasthe options of touching the turbo mode input display element to returnto the previous mode of operation or touching the power input displayelement to power off the ATS.

Once in the “night” mode, the control subsystem continues to operate theATS in the same mode of operation, but the content of the display isreduced to minimize light emissions. In the night mode, the night modeinput display element is illuminated in the “present” state and powerinput display element is illuminated in the “on” state. The remainingdisplay elements are off. In this mode, the operator has the options ofdisabling night mode (i.e. re-enabling the display in accordance withthe current mode of operation) by touch the night mode input displayelement or powering off the ATS by touching the power input displayelement.

D. Front Cover

As noted above, the ATS 10 includes a removable front cover 32 thatcloses the front of the ATS 10 covering the filters 100, 102 and 104, aswell as the electronics module 14 and blower 56. The front cover 32 ofthe illustrated embodiment defines a central inlet 106 a and is offsetfrom the ATS housing 110 so that they cooperatively define a side inlets106 b-c. An inlet trim piece 98 may be fitted into the central inlet 106a. In the illustrated embodiment, the front cover 32 is convex creatinga relatively large head space between the rear surface of the frontcover 32 and the installed filters. This may allow air to enter morefreely into the ATS 10 through the central inlet 106 a.

In this embodiment, the front cover 32 also forms the interface surfaceof the “dead front” display 16. As such, the front cover 32 of thisembodiment is translucent (e.g. not entirely transparent or entirelyopaque with respect to visible light) at least in the region of theelectronics module 14 overlying the LED array 62, light duct array 72and screens 74 a and 74 b. The front cover 32 may be manufactured from atranslucent polymer (e.g. a molded thermoplastic) having a paint coatingor film coating that provides the desired translucency. In oneembodiment, the front cover 32 is covered by an in-mold film process. Tofacilitate proper appearance of the “dead front” display, it may benecessary to carefully control the paint or film coating applied to thefront cover 32. Alternatively, the front cover 32 may be manufacturedfrom a translucent material, such as a molded translucent thermoplastic.

In the illustrated embodiment, the front cover 32 is configured to allowone-handed removal and installation. The front cover 32 includes amechanical attachment point at the top and a pair of magnetic attachmentpoints at the bottom. In the illustrated embodiment, the mechanicalattachment point registers on the electronics module 14. This helps toensure proper alignment between the front cover 32 and the underlyingcomponents of the display 16, which may help to ensure proper appearanceand operation of the “dead front” display. Although the mechanicalattachment point registers off the electronics module 14 in theillustrated embodiment, it may register off other structures inalternative embodiments.

Referring now to FIGS. 19A and 19B, the mechanical attachment point ofthe illustrated embodiment includes a lip 36 that extends from the frontcover 32 and is configured to catch on the electronics module 14. In theillustrated embodiment, the lip 36 extends approximately the full widthof the electronics module 14, except that it may include a gap 37 (SeeFIG. 2) aligned with the dust sensor inlet 82. The lip 36 of thisembodiment is oriented at an angle that allows the lip 36 to catch onthe electronics module 14 as the front cover 32 is lowered into place.It allows the front cover 32 to be disengaged from the ATS housing 110by sliding it upwardly with respect to the ATS housing 110. This upwardsliding motion not only disengage the lip 36 from the electronics module14, but may also simultaneously disengage the magnets 90 from theattachment plates 92 in the ATS housing 110 (as discussed below),thereby facilitating removal. The size, shape and configuration of thelip 36 may vary from application to application. In alternativeembodiments, the lip may be replaced by essentially any other male orfemale structure capable of engaging with the electronics module 14.

In this embodiment, the front cover 32 includes two magnetic attachmentpoints position toward opposite sides of the bottom of the front cover32. Each magnetic attachment point includes a magnet 90 carried by thefront cover 32 and a magnetically attractive plate 92 mounted the ATShousing 110 (See FIGS. 20A and 20B). The magnets 90 may be disc-shapedrare-earth magnets that are mounted in corresponding sockets 94protruding from the rear of the front cover 32. The plates 92 may besized and shaped so that the magnets 90 substantially disengage from theplates 92 when the front cover 32 is slid upward a sufficient distancefor the lip 36 to clear the electronics module 14. The number, size,shape and configuration of the magnets and plates may vary fromapplication to application as desired. For example, stronger magnets ormore magnetic attachment points may be used to increase the forcerequired to remove the front cover 32.

In use, the front cover 32 may be removed and installed in various ways.One option for removing the front cover 32 is shown in FIG. 17A. Withthis option, the front cover 32 is slid upward with respect to the ATShousing 110 a sufficient distance for the lip 36 to clear the electronicmodule 14, and then the top of the front cover 32 is tilted away fromthe ATS housing 110 to overcome any remaining magnetic attraction at themagnetic attachment points. The front cover may be installed usingessentially the reverse process. Another option for removing the filteris shown in FIG. 17B. With this option, the operator reaches down andpulls the bottom of the front cover 32 away from the ATS housing 110until the magnets 90 disengage from the plates 92. The operator thenlift the front cover 32 a sufficient distance for the lip 36 to clearthe electronics module 14. The front cover 32 may be installed bydraping the top of the front cover 32 over the electronics module 14 andthen swinging the bottom of the front cover 32 toward the ATS housing110 until the magnets 90 engage the plates 92.

The front cover 32 may include an interlock magnet (not shown) thatallows the control subsystem 60 to recognize when the front cover 32 ininstalled and when it is removed. The interlock magnet may be locatedtoward the top of the front cover 32 where it can be sensed by ahall-effect or other magnetic field sensor that is incorporated into theelectronics module 14. As an alternative to using a separate interlockmagnet, the ATS 10 may include a hall-effect sensor (or other magneticfield sensor) that is positioned to allow it to recognize the presenceor absence of the front cover 32 based on one of the magnets 90 used toattach the front cover 32 to the ATS housing 110.

If desired, the electronic module 14 may include LEDs or other lightsources that can be engage to provide illumination that is visiblethrough the central inlet opening 106 a and/or at the side of frontcover 32. This illumination may be provided as accent lighting or mayhave a functional purpose. For example, the control system 12 mayprovide blue illumination or no illumination when the ATS 10 isoperating properly and does not require maintenance, and it may providered illumination when operator intervention is required. This may occurwhen it is necessary to change or clean a filter, or when there has beena system error. The red illumination may flash when a particular urgentissue exists.

As noted above, the front cover 32 incorporates an appropriate level oftranslucency to produce a “dead front” display 16. As an alternative,the “dead front” display may be produced by a translucent componentdisposed below the front cover 32, such as a separate panel disposedover the electronics module 14. In such embodiments, the front cover 32may be transparent or sufficiently translucent to allow the underlying“dead front” display to be seen through the front cover 32.

E. Mobility Features

In the illustrated embodiment, the ATS 10 may be configured to interfacewith one of a plurality of interchangeable bases 40. In the illustratedembodiment, the bases 40, 40′ and 40″ are secured to the ATS housing 110using screws or other fasteners. The number and location of fastenersmay vary from application to application. As an alternate or in additionto fasteners, the ATS housing 110 and bases 40, 40′ and 40″ may beprovided with snap features that allow the desired base to besnap-fitted to the ATS 10.

Different bases 40 may provide different structure for receiving thepower cord 42 and/or different structure for supporting the ATS 10. AnATS 10 with three alternative bases 40, 40′ and 40″ are shown in FIGS.21 and 22. In general, base 40 has a bobbin 44 for manually winding thepower cord 42 and a plurality of fixed feet 46; base 40′ has a bobbin44′ for manually winding the power cord 42′ and a plurality of caster46′; and base 40″ include a cord retraction assembly 45 with anautomatic take-up reel (not shown) and a combination of fixed feet 46″and a roller 47″. Although the illustrations show an embodiment of abobbin that extends laterally across a portion of the ATS housing 110,the term “bobbin” is intended to include any individual feature orcombination of features provided as a structure around which the powercord 42 may be wrapped.

In the illustrated embodiment, the ATS 10 also includes a handle 48disposed on the top rear of the ATS housing 110. The handle 48 of thisembodiment extends essentially the full width of the ATS 10 to allow theATS 10 to be grabbed in the center by a single hand or toward oppositesides by two hands. In this embodiment, the handle 48 may include arelatively deep central pocket of sufficient depth to receive anoperators fingers up to approximately two knuckles and relativelyshallow side pockets of sufficient depth to receive an operator'sfingers up to approximately the first knuckle. The handle 48 may be aone-piece component that is secured to the ATS housing 110, for example,by fastener, or it may be integrally formed with other parts of the ATShousing 110.

With regard to base 40, the handle 48 may be used to lift the ATS 10when moving it from one location to another. With regard to base 40′,handle may be used to grasp the ATS when rolling it from location tolocation on casters 46′. With regard to base 40″, the handle 48″ can beused to tilt the ATS 10 forward onto the roller 47″ and to roll the ATS10 from one location to another.

F. Filter Retainer Assembly

As noted above, the ATS 10 includes a prefilter 100, a particulatefilter 102 and a carbon filter 104 that are removably fitted into afilter housing 112. The system includes a filter retainer assembly 50that facilitates quick and secure installation and removal of thefilters. In the illustrated embodiment, the filter retainer assembly 50includes a catch 52 and a pair of clips 54 integrated into the frame ofthe particulate filter 102, as well as a locking protrusion 126integrated into the ATS housing 110. Because the prefilter is secured tothe particulate filter 102 and the particulate filter 102 covers thecarbon filter 104, the filter retainer assembly 50 effectively securesall three filters 100, 102 and 104. In the illustrated embodiment, theclips 54 are configured so that they draw the particulate filter 102tightly into the filter housing 112 as they are closed. This helps tocompress a face seal 118 on the particulate filter 102 against shoulder114 to facilitate an airtight seal.

Referring now to FIG. 29B, the catch 52 is disposed at the bottom centerof the frame of the particulate filter 102. The catch 52 of thisembodiment is molded integrally with the frame of the particulate filter102, but it may alternatively be formed separately and affixed to theframe. The catch 52 of the illustrated embodiment has a quarter-roundcross-section that may facilitate installation and removal from acorresponding void 120 in the filter housing 112. The number, size,shape and configuration of the catch 52 and void 120 may vary fromapplication to application as desired. For example, the positions of thecatch 52 and void 120 can be reversed with the catch extend from thefilter housing 112 and the void being defined in the particulate filter102.

As perhaps best shown in FIGS. 29A and 29B, the clips 54 are rotatablymounted to opposite sides of the frame of the particulate filter 102.Each clip 54 may include a handle 122 and a hook 124. The handle 122 isconfigured to provide structure that can be used by an operator torotate the clips 54. The hook 124 is configured to engage the lockingprotrusion 126 as the clip 54 is rotated into the closed position. Thehook 124 and locking protrusion 126 are configured such that there isinterference between the two for a short distance as the clip 54approaches the closed position. This creates a snap-fit that helps tosecure clip 54 in the closed position. Further movement toward theclosed position cause the hook 124 to flex creating resistance tofurther movement toward the closed position. As the clip 54 continuestoward the closed position, the hook 124 clears the region ofinterference and begins to return to its original un-flexed condition.This pushes the clip 54 the remaining way into the closed position. Inthe illustrated embodiment, the location and configuration of the hook124 with respect to the pivot location is selected so that the clips 54provide a cam-like function that pulls the particulate filter 102 intothe filter housing 112 as the clips 54 are closed. Operation of the clip54 is shown in FIGS. 30A-D. In FIG. 30A, the clip 54 is shown in theopen position. In this position, the hook 124 is disengaged from thelocking protrusion 126. FIG. 30B shows the clip 54 in a partially closedposition. As can be seen, the hook 124 has moved into engagement withthe locking protrusion 126. In this position, the particulate filter 102has been draw partially into the filter housing 112 as can be seen bycomparison with reference line R. FIG. 30C shows the clip 54 movedfarther toward the closed position. In this view, the hook 124 hasengaged the locking protrusion 126 and has begun to flex outwardly awayfrom the locking protrusion 126 due to interference between the two. Ascan be seen, the particulate filter 102 has been drawn farther into thefilter housing 112. In FIG. 30D, the clip 54 is in the closed position.In this position, the hook 124 has moved past the region of interferenceand is fully engaged with the locking protrusion 126. The particulatefilter 102 has been drawn fully into the filter housing 112.

Removal of the particulate filter 102 is described in connection withFIGS. 28A-D. In the first illustration, the front cover 32 and prefilter100 are removed to provide access to the particulate filter 102 (SeeFIG. 28A). In the illustrated embodiment, it is not necessary to removethe prefilter 100 from the particulate filter 102. In the nextillustration, each of the clips 54 has been rotated from the closed toopen position (See FIG. 28B). This disengages the hooks 124 from thelocking protrusions 126 in the filter housing 112. The next illustrationshows the top of the particulate filter 102 being tilted away from thefilter housing 112 (See FIG. 28C). The final illustration shows thefilter 102 being lifted from the filter housing 112 to disengage catch52 from void 120 (See FIG. 28D). The particulate filter 102 can beinstalled using essentially the reverse process.

The design and configuration of the clips may vary from application toapplication. Alternative clips 54′ and 54″ are shown in FIGS. 31A-D and32A-D. In both of these alternative embodiment, the filter retainerassembly further includes locking pins 128′, 128″ that secure the clips54′, 54″ in the closed position. The locking pins 128′, 128″ protrudefrom the particulate filter 102, but could alternatively protrude fromthe filter housing 112, if desired. Alternative clip 54′ includes atooth 130′ protruding from the outside edge of the clip 54′. The tooth130′ is configured to engage a corresponding recess 132′ in locking pin128′ when the clip 54′ is in the closed position. Together, the tooth130′ and locking pin 128′ snap-lock the clip 54′ in the closed position.Operation of the clips 54′ is shown with reference to FIGS. 31A-D. InFIG. 31A, the clip 54′ is shown in the open position. In this position,the hook 124′ is disengaged from the locking protrusion 126′. FIG. 31Bshows the clip 54′ in a partially closed position. As can be seen, thehook 124′ has moved into engagement with the locking protrusion 126′. Inthis position, the particulate filter 102 has been draw partially intothe filter housing 112 as can be seen by comparison with reference lineR. FIG. 31C shows the clip 54′ moved farther toward the closed position.In this view, the hook 124′ has further engaged the locking protrusion126′ and drawn the filter 102 farther into the filter housing 112. InFIG. 31D, the clip 54′ is in the closed position. In this position,tooth 130′ has become seated in recess 132′ and the particulate filter102 has been drawn fully into the filter housing 112. Theinterrelationship between the tooth 130′ and the locking pin 128′ helpsto secure the clip 54′ in the closed position.

Alternative clip 54″ is similar to clip 54′. In this embodiment, theclip 54″ includes a series of contours that interact with the lockingpin 128″ to control movement and feel of the clip 54″. Morespecifically, the clip 54″ includes a stop 134″ and a seat 136″ that areconfigured to engage with the locking pin 128″ when the clip 54″ is inthe opened or closed positions. The stop 134″ is configured to engagethe locking pin 128″ when the clip 54″ is in the fully open position.The stop 134″ helps to limit the range of motion of the clip 54″. Theseat 136″ is configured to interlock with the locking pin 128″ when theclip 54″ is in the fully closed position. The leading edge of the seat136″ may be raised to create a snap-fitting interaction as the clip 54″is closed or opened. Operation of clips 54″ is now described withreference to FIGS. 32A-D. In FIG. 32A, the clip 54″ is shown in the openposition. In this position, the hook 124″ is disengaged from the lockingprotrusion 126″ and the stop 134″ is engaged with the locking pin 128″.FIG. 32B shows the clip 54″ in a partially closed position. The hook124″ has moved into engagement with the locking protrusion 126″. In thisposition, the particulate filter 102 has been draw partially into thefilter housing 112 as can be seen by comparison with reference line R.FIG. 32C shows the clip 54″ moved farther toward the closed position. Inthis view, the hook 124″ has further engaged the locking protrusion 126″and drawn the filter 102 farther into the filter housing 112. Also, theleading edge of the seat 136″ has begun to engage the locking pin 128″.In FIG. 32D, the clip 54″ is in the closed position. In this position,the locking pin 128″ and seat 136″ are fully engaged and the particulatefilter 102 has been drawn fully into the filter housing 112. Therelationship between the locking pin 128″ and the seat 136″ helps tosecure the clip 54′ in the closed position.

G. Alternative Embodiment

The present invention is capable of implementation in a wide variety ofalternative embodiments. For example, one alternative embodiment isshown in FIG. 33A-53D. Except to the extent described below or shown inthe accompanying drawings, this alternative embodiment is generallyidentical to the embodiment shown above in FIGS. 1A-20B. To facilitatedisclosure, this alternative embodiment will be described with referencenumerals that are identical to the reference numerals used in connectionwith ATS 10, except preceded by the number “4.” For example, thealternative ATS is designated by reference numeral 410 (analogous to ATS10) and the ATS housing of the alternative ATS is designated byreference numeral 4110 (analogous to ATS housing 110).

Referring now to FIGS. 33A, 33B and 34, ATS 410 generally includes ahousing assembly that houses a control system 412, a blower 456, aprefilter 4100, a particulate filter 4102 and an activated carbon filter4104. The ATS 410 includes untreated air inlets 4106 a-c in the frontthrough which untreated air can be drawn into the system and an airoutlet 4108 in the rear through which treated air can be returned to theenvironment (See FIG. 44). In operation, the control system 412 operatesthe blower 456 to draw untreated air into the ATS 410 through the inlets4106 a-c, move the untreated air successively through the three filters4100, 4102 and 4104 and then discharge the treated air through theoutlet 4108. The size, shape and configuration of the inlet, outlet andinternal flow path may vary from application to application as desired.

Referring again to FIG. 34, the housing assembly generally includes amain housing 4110, a filter housing 4112 and a top housing 4113. Themain housing 4110 primarily forms the rear, sides and bottom of the ATS410. As with ATS 10, the filter housing 4112 is affixed to the mainhousing 4110 to close the front of the ATS 410 and provides seats forthe particulate filter 4102 and the carbon filter 4104. As perhaps bestshown in FIG. 49, the top housing 4113 is attached to the back side ofthe filter housing 4112, for example, by screws (not shown). The tophousing 4113 includes an integral handle 448. In this embodiment, thehandle 448 includes a central section that can be gripped by a singlehand and a pair of side sections that can be gripped with both hands. Inthe illustrated embodiment, the main housing 4110 includes a cord wrap444 (or bobbin) for manually winding the power cord (not shown) (SeeFIG. 33B). In this embodiment, the cord wrap 444 includes a pair offingers 445 spaced apart on opposite sides of power cord input port 447.The size, shape and configuration of the fingers 445 may vary depending,for example, on the characteristics of the power cord. As shown, thecord wrap 444 may be positioned in a recess in the main housing 4110 sothat it does not protrude and therefore does not increase the profile ofthe ATS 410.

ATS 410 includes a removable front cover 432 that closes the front ofthe ATS 410 covering the display 416 and the filters 4100, 4102 and4104. As can be seen in various Figs, such as FIGS. 33 a, 44 and 46, thefront cover 432 defines a central inlet 4106 a and is spaced from thefilter housing 4112 so that the front cover 432 and filter housing 4112cooperatively define side inlets 410 b-c. The front cover 432 of theillustrated is manufactured from an opaque plastic material, forexample, by injection molding. The front cover 432 may alternative bemanufactured from a wide range of alternative materials. In thisembodiment, the front cover 432 includes a window 433 that covers thedisplay 416. The window 433 is fitted into a corresponding opening 435defined in the front cover 432. To conceal display elements that are notilluminated, the window 433 of this embodiment is translucent at leastin the region or regions overlying the display elements 418. The window433 may be manufactured from a translucent polymer (e.g. a moldedthermoplastic) having a paint coating or film coating that provides thedesired translucency. In one embodiment, the window 433 is covered by anin-mold film process. To facilitate proper appearance of the “deadfront” display, it may be necessary to carefully control the paint orfilm coating applied to the window 433. Alternatively, the window 433may be manufactured from a translucent material, such as a moldedtranslucent thermoplastic.

In the illustrated embodiment, the front cover 432 is configured toallow one-handed removal and installation. The front cover 432 includesa mechanical attachment point at the top and a pair of magneticattachment points at the bottom. Referring now to FIGS. 45A, 45B and 46,the mechanical attachment point of the illustrated embodiment includes acatch 436 (or lip) that extends from the front cover 432 and isconfigured to fit in a seat 437 in the electronics module 414 or in thestructure surrounding the electronics module 414. The catch 436 may beseparately manufactured and affixed to the front cover 432 (See FIG. 46)or it may be integrally formed with the front cover 432 (not shown). Thecatch 436 of this embodiment is oriented at an angle that allows thecatch 436 to be retained in the seat 437 as the front cover 32 isclosed. It allows the front cover 432 to be disengaged from the ATShousing 4110 by sliding it upwardly with respect to the ATS housing4110. This upward sliding motion not only disengage the catch 436 fromthe seat 437, but may also simultaneously disengage the magnets 490 fromthe attachment plates 492 in the ATS housing 4110 (as discussed below),thereby facilitating removal. The size, shape and configuration of thecatch 436 may vary from application to application. In alternativeembodiments, the catch 436 may be replaced by essentially any other maleor female structure capable of engaging with the seat 437 or othersimilar structure in or around the electronics module 414.

The front cover 432 of this embodiment includes two magnetic attachmentpoints position toward opposite sides of the bottom of the front cover432. Each magnetic attachment point includes a magnet 490 carried by thefront cover 432 and a magnetically attractive plate 492 mounted the ATShousing 4110 (See FIG. 48). The magnets 490 may be disc-shapedrare-earth magnets that are mounted in corresponding sockets 494protruding from the rear of the front cover 432. In this embodiment, theplates 492 are configured to perform two functions—(i) provide amagnetically attractive structure for the magnets 490 and (ii) rotatablysupport a roller 447. In this embodiment, each plate 492 is generallyL-shaped having a first leg 493 that is positioned to receive the magnet490 and a second leg 495 that rotatably supports the roller 447. Thefirst leg 493 and the second leg 495 are generally planar, but mayinclude ribs or other contours to enhance strength or to interfit withadjacent components of the ATS 410. The first leg 493 includes a pair ofmounting tabs 491 that extend rearwardly and allow the plate 492 beaffixed to the housing 4110, for example, by screws (not shown). Thesecond leg 495 defines a circular opening 497 configured to rotatablyreceive the axle (or shaft) of the roller 447. In use, the two plates492 trap opposite end of the shaft or axle of the roller 447. In thisembodiment, the plate 492 is stamped from sheet stock and is configuredto be ambidextrous so that the same plate 492 can be used on oppositesides of the ATS 410 simply by flipping the plate 180 degrees. Forexample, the mounting tabs 491 may be centered vertically and each tab491 may be spaced the same distance from the corresponding end of thefirst leg 493. Also, the circular opening 497 may be vertically on thesecond leg 495.

In this embodiment, the control system 412 includes a capacitive sensorthat allows the system to recognize when the front cover 432 ininstalled and when it is removed (discussed in more detail below). Thiseliminates the need for any interlock magnet or magnetic field sensorused to determine presence of the front cover as discussed above inconnection with ATS 10.

As noted above, ATS 410 includes prefilter 4100, particulate filter 4102and carbon filter 4104. Like ATS 10, the filters are secured in ATS 410by a filter retainer assembly 450 incorporated into the particulatefilter 4102. More specifically, the filters are installed by fitting thecarbon filter 4104 into carbon filter seat in the filter housing 4112,fitting the particulate filter 4102 into the particulate filter seat inthe filter housing 4112 over the carbon filter 4104, securing theparticulate filter 4102 using the filter retainer assembly 450 andaffixing the prefilter 4100 to the particulate filter 4102. In thisembodiment, the filter retainer assembly 450 differs somewhat from thefilter retainer assembly 50 discussed above in connection with ATS 10.In this embodiment, the bottom of the particulate filter 4102 is held bya catch 452 that is fitted into a void 4120 in the filter housing 4112,and the top is held by a clip 454 (or latch) that interlocks with alocking protrusion 4126 extending from the filter housing 4112. FIGS.52A-D illustrate the process of removing the particulate filter 4102from the ATS 410. FIG. 52A shows the particulate filter 4102 installedwith the clip 454 in the closed position. FIG. 52B shows the particularfilter 4102 installed with the clip 454 rotated into the open position.FIG. 52C shows the top of the particulate filter 4102 tilted away fromthe ATS 410. The tilting movement of the filter 4102 also disengages (orlargely disengages) the catch 452 from the void 4120. FIG. 52D shows theparticulate filter 4102 removed from the ATS 410. In the illustratedembodiment, the clip 454 is configured to draw the particulate filter4102 tightly into the filter housing 4112 as it is closed. This helps tocompress a face seal (not shown) on the particulate filter 4102 againstshoulder 4114 to facilitate an airtight seal.

Referring now to FIGS. 51A-C, the catch 452 is disposed at the bottomcenter of the frame of the particulate filter 4102. The catch 452 ofthis embodiment is molded integrally with the frame of the particulatefilter 4102, but it may alternatively be formed separately and affixedto the frame. The catch 452 of the illustrated embodiment has aquarter-round cross-section that may facilitate installation and removalfrom a corresponding void 4120 in the filter housing 4112. The number,size, shape and configuration of the catch 452 and void 4120 may varyfrom application to application as desired.

In this embodiment, the clip 454 is rotatably mounted near the topcenter of the frame of the particulate filter 4102. The clip 454includes a handle 4122, a tooth 4130 and a hook 4124. The tooth 4130 isconfigured to engage the locking pin 4128 as the clip 454 is rotatedinto the closed position. More specifically, interference between thetooth 4130 and the locking pin 4128 causes the clip 454 to snap lockinto the closed position. Further, the hook 4124 is configured to engagethe locking protrusion 4126 as the clip 454 is rotated into the closedposition. In the illustrated embodiment, the location and configurationof the hook 4124 and the locking protrusion 4126 are selected so thatthe clip 454 provides a cam-like function that pulls the particulatefilter 4102 into the filter housing 4112 as the clip 454 is closed.Operation of the clip 454 is shown in FIGS. 53A-D. In FIG. 53A, the clip454 is shown in the open position with the hook 4124 disengaged from thelocking protrusion 4126. FIG. 53B shows the clip 454 rotated clockwiseinto a partially closed position. FIG. 53C shows the clip 454 rotatedfurther clockwise into a position in which the tooth 4130 is about toengage the locking pin 4128. Finally, FIG. 53D shows the clip 454 in theclosed position. As can be seen, the tooth 4130 has moved past thelocking pin 4128 and now resists movement of the clip 454 out of theclosed/locked position. Also, the hook 4124 has moved into engagementwith the locking protrusion 4126. Interaction between the hook 4124 andthe locking protrusion 4126 pulls the particulate filter 4102 fully intothe filter housing 4112.

In this embodiment, the prefilter 4100 is secured to the particulatefilter 4102 using a somewhat different configuration than incorporatedinto ATS 10. As shown in FIG. 34, the prefilter frame 4116 includes apair of tabs 4304 on the bottom and a pair of slotted tabs 4306 on thetop. As shown in FIGS. 51A-C, the particulate filter 4102 includes apair of slotted feet 4300 on the bottom and a pair of fingers 4302 onthe top. The fingers 4302 may be configured to snap-lock into engagementwith the slotted tabs 4306. For example, the fingers 4302 may be angledupwardly from the particulate filter frame. In use, the prefilter 4100is secured to the particular filter 4102 by first inserting the tabs4304 on the bottom of the prefilter frame 4116 into the slots in feet4300 on the bottom of the particulate filter 4102 and then tilting thetop of the prefilter 4100 inwardly toward the top of the particulatefilter 4102 to snap fit the slotted tabs 4306 over the fingers 4302 onthe top of the particulate filter 4102.

Control System

ATS 410 includes a control system 412 that controls operation of the ATS410 and provides a user interface for displaying information andreceiving input from the operator. The primary functions of the controlsystem 412 are to control the speed at which the ATS 410 operates totreat air based on sensed parameters or operator input, to track theusage of filters, to notify the operator of the mode, motor speedsetting and filter life and to accept operator commands. The controlsystem 412 includes a user interface that is implemented as a “deadfront” display 416 that displays information and receives operator inputrelevant to operation and maintenance of the system. The display 416includes a plurality of display elements 418 that are visible only whenilluminated to provide a dynamic display that varies to provideinformation and to present control options that are available at anygiven time (Compare FIGS. 40 and 41). As with display 16 discussedabove, the display 416 of ATS 410 includes informative display elements418 a that are illuminated to provide information regarding the statusof the ATS or a monitored characteristic, and input display elements 418b that incorporate a touch sensor to allow an operator to provide inputto the control system 412 (See FIG. 41). In addition to allowing userinput, input display elements 418 b may also provide informationregarding the status of the ATS, such as mode of operation and blowerspeed. Display 416 includes essentially the same display elements 418 asdisplay 16 discussed above, except that the display elements 418 arepositioned differently and display 416 include one additional displayelement to show when the display 416 is using an integrated WiFitransceiver to communication with an external network.

The control subsystem 460 includes control circuitry and firmware thatis configured to operate the ATS 410 and to coordinate the collection ofdata from various other subsystems, including the capacitive touchsensor array 464, the dust sensor 480, the RFID subsystem 468 and thewireless communication subsystem 470. The various modes of operation ofthe system are described in more detail below. Referring now to theschematic representation of FIG. 36, the electronics module 414generally includes a distributed control arrangement with a primaryapplication controller 510, a touch detection controller 512, an LEDdriver controller 514 and an RFID controller 516. The primary controller510 is connected to the dust sensor 480, the RFID subsystem 468(including the RFID controller 516 and an RFID antenna 518), thewireless communication subsystem 470 (including a Bluetooth module 520and a WiFi module 522) and the electrical components that make up thedisplay 416 (including the LED driver controller 514 and the touchdetection controller 512). The primary controller 510 is also coupled tothe blower motor power supply 530 to allow the primary controller 510 tocontrol blower speed and in some application to receive feedback fromthe blower motor power supply 530. The primary application controller510 is also coupled to a buzzer 524 for providing audible output, a UARTheader 526 for diagnostics and non-volatile memory, such as EEPROM 528,for storage of preprogrammed operational default values as well ashistorical operational data, such as the life of the filters, time ofuse, counters and other variables that might be used in connection withoperation of the ATS 410. The touch detection controller 512 iselectrically connected to the capacitive touch keys, which are definedby a plurality of capacitive traces 532, and to an ambient light sensor534. In use, the touch detection controller 512 may monitor thecapacitive traces and the ambient light sensor 534, and providetouch/proximity information and ambient light information to the primaryapplication controller 510. The LED driver controller 514 is coupled tothe LED array 462. In operation, the LED driver controller 514 mayilluminate the individual LEDs in the LED array 462 in accordance withcommands received from the primary application controller 510.

The control system 412 is incorporated into a self-contained electronicsmodule 414. Referring now to FIGS. 37-39, the electronics module 414 forATS 410 generally includes a base 4150, a dust sensor cover 4152, anelectronics assembly 550 and a screen 474. In this embodiment, the base4150 mounts to the filter housing 4112 and provides a structure on whichthe various components of the electronics module 414 are mounted. Thebase 4150 includes an electronics assembly seat (not shown) that allowsthe electronics assembly 550 to be mounted to the underside of the base4150, for example, by screws (not shown) that extend through mountingtabs 552. The base 4150 also includes a dust sensor compartment 560 thatseats the dust sensor 480 and provides a flow path to direct air overthe dust sensor 480. The flow path generally includes a sensor inlet482, a sensor tunnel 484 and a sensor outlet 486. The sensor inlet 482may be closed by a dust sensor screen 562 to prevent large particles forfouling the dust sensor 480. The dust sensor 480 may be enclosed withina pair of rubber shell halves 488 a and 488 b that create a leaktightseal around the dust sensor 480. The dust sensor cover 4152 may define aplurality of air flow apertures 564 that allow air to flow out of thedust sensor compartment 560 to a position upstream from the particulatefilter 4102. It should be noted that the dust sensor flow path isdescribed for a system in which the partial vacuum created by the blower456 draws air into the ATS 410 along the dust sensor flow path.Alternatively, air may flow through the dust sensor flow path in reverseif the air discharged through the air outlet 4108 by the ATS 410 createsa greater partial vacuum at the sensor inlet 482 than the blower createsat the air flow apertures 564 in the dust sensor cover 4152.

The electronics assembly 550 for ATS 410 generally includes a bottom PCB566, a light guide 472 and a top PCB 568 (See FIG. 39). The bottom PCB566 may support the bulk of the circuitry and circuit components,including the various controllers and the LED array 462. The LED arraymay include a plurality of individual LEDs 462 a that can be selectivelyilluminated when appropriate. Each LED 462 a may include a single LED ormultiple LEDs that provide various illumination options. In thisembodiment, each LED associated with the filter life display elementsmay include a red LED and a green LED; each LED associated with the ATSdisplay element, the power display element and the line display elementsmay include a white LED; each LED associated with the blower speeddisplay elements, the turbo mode display element, the WiFi displayelement and the dust sensor cloud sensor element may include a blue LEDand a white LED; the LED associated with the first dust level displaymay include a red LED, a green LED and a yellow LED; each LED associatedwith the second and third dust levels may include a red LED and a yellowLED; each LED associated with the fourth and fifth dust levels mayinclude a red LED and each LED associated with the night mode displayelement may include a red LED and a white LED. As with ATS 10, the LEDarray 462 may be replaced or supplemented with other types of lightsources, such as OLED, laser and EL light sources.

The light guide 472 provides a mounting structure for the PCBs 566 and568 and includes a plurality of light ducts 472 a that convey light fromthe LED array 462 on the bottom PCB 566 through openings in the top PCB568 to illuminate the display elements 418 on the screen 474. The lightducts 472 a are configured to create light flow paths from the LEDs 462a to the corresponding display elements 418. The light ducts 472 a maybe isolated from one another to prevent bleeding of light from one LED462 a to an adjacent display element 418. The surfaces of the lightducts 472 a may be coated or textured to create diffuse light.

The top PCB 568 is mounted atop the light guide 472. The top PCB 568defines a plurality of light openings 570 and a plurality of traces 532that are function as capacitive touch sensors. In this embodiment, thetop PCB 568 includes a separate light opening 570 for each displayelement 418 (See FIGS. 38 and 39). The size, shape and configuration ofthe light openings 570 may vary from application to applicationdepending, for example, on the desired lighting effect. As noted above,the control system 410 includes a plurality of capacitive touch sensors464. The design and configuration of the capacitive touch sensors mayvary from application to application. For example, each capacitive touchsensors may include a pair of electrodes and touches may be recognizedby monitoring mutual capacitance between the electrode pair. As anotherexample, each capacitive touch sensor may include a single electrode andtouches may be recognized by monitoring the self-capacitance of theelectrode. Referring now to FIG. 39, a trace 532 (or pair of traces)extends around each light opening 570 that is associated with an inputdisplay element 418 b. More specifically, a conductive trace 532 (orpair of traces), such as a copper conductive element is provided aboutthe periphery of each light opening 570 associated with an input displayelement 418 b. The size, shape, extent and other aspects of theconfiguration of each conductive trace 532 may vary from application toapplication to provide the desired touch sensor characteristics.Additionally, the top PCB 568 may include an additional conductive trace532 b intended to sense proximity of a user. As shown in FIG. 39, theproximity sensor trace 532 b may be a relatively large trace thatextends along a significant portion of the top PCB 568. In use, thetouch detection controller 512 may monitor the various conductive traces532 to determine when a touch or proximity event occurs.

In this embodiment, the control system 412 includes a single screen 474that covers all of the display elements 418. The screen 474 is alaminated structure that generally includes a diffusing layer and amasking layer. The diffusing layer diffuses light produced by the LEDs.The masking layer masks the light to create the desired graphic,including various opaque and translucent materials, such as inks,paints, films, and other adhesive layers. In the illustrated embodiment,the masking layer is disposed on the outer surface of the diffusinglayer opposite the LEDs or other light source, but it may be locatedelsewhere, if desired. Although the diffusing layer and masking layerare part of a single laminated construction in the illustratedembodiment, they may alternatively be separate components. For example,they may be separately manufactured and positioned adjacent to oneanother during assembly of the display 416.

Operation of the ATS 410 will now be described with reference to FIGS.42 and 43. FIG. 42 is an illustration of the display 416 showing theoutline of all display elements 418, including informative displayelements 418 a and input display elements 418 b. FIG. 43 shows a seriesof illustrations of the display 416 a-m in different modes of operation.In the illustrated embodiment, the display 416 can be in three differentstates when powered off. When the ATS 410 is unplugged or is otherwisenot receiving power, the display is entirely blank as shown by display416 a. When the ATS 410 is plugged in, but not powered and no user isproximate, display elements 618 a-c are illuminated to display a lineacross the display 416, as shown by display 416 b. When the ATS 410 isplugged in, but not powered and a user is proximate, display elements618 a-c and 608 are illuminated to display a line and a power icon, asshown by display 416 c.

The control system 412 may determine a user is proximate by monitoringcapacitive trace 532 b. The control system 412 and proximity trace 532 bmay be configured to determine when a user is proximate using a varietyof alternative approaches. In the illustrated embodiment, the controlsystem 412 and proximity trace 532 b are configured to determine that auser is in proximity when the user comes within approximately twelveinches of the trace 532 b, for example, by waving the user's hand overthe display 416 within about twelve inches of the window 433. The size,shape and configuration of the trace 532 b and/or the sensitivity of thecontrol system 412 to changes sensed in the trace 532 b may be varied toincrease or decrease how close a user must be for the system to concludethat a user is proximate. The control system 412 may determine that auser is not proximate based on the passage of time after the display 416has received user input. For example, the control system 412 may reset acountdown timer each time that user input event occurs. A user inputevent may occur each time that a user touches a touch key trace 532 oreach time that a user comes within sufficient proximity of the proximitytrace 532 b. If the countdown timer reaches zero, the control system 412will conclude that no user is proximate and adjust the display 416accordingly. The control system 412 may then begin continue to monitorthe proximity trace 532 b to determine when a user comes back withinsufficient proximity to the display 416. In addition, the control system412 may also conclude that a user is in proximity if a touch key trace532 is touched by a user.

Once powered on, the display 416 is capable of operating in a variety ofalternative states. When the ATS 410 is in the manual mode and a user isproximate, all of the display elements are illuminated as appropriate,as shown by display 416 d. Display elements 618 a-c are illuminated toshow the line. Display element 608 is illuminated to show the powericon. Display element 614 is illuminated to show the night mode icon.Because the ATS 410 is not in night mode, display element 614 isilluminated white. Display element 606, including the dust icon 606 aand appropriate dust level indicators 606 b are illuminated. Because theATS 410 is not in auto mode, the dust icon 606 a is illuminated white.Also, because the dust level is sufficiently low, only a single dustlevel indicator 606 b is illuminated, and it is illuminated green.Display element 616, including the blower icon 616 a and appropriateblower speed indicators 616 b are illuminated. Because the ATS 410 is inmanual mode, the blower icon 616 a is illuminated blue. All of theblower speed indicators 616 b are illuminated with the indicatorsrepresenting actual blower speed illuminated blue and available higherblower speeds illuminated white. Display element 612 is illuminatedwhite to indicate that the ATS 410 is not in turbo mode. The filter lifedisplay elements 600, 602, 604, including the ATS icon 605, areilluminated. In this example, all of the filters have remaining life andare therefore illuminated green. The ATS icon 605 is illuminated white.Finally, the display element 620 is illuminated to display the WiFiicon. In this example, no WiFi transfer is occurring so the WiFi icon isilluminated white. When the operator is no longer in proximity, thedisplay 416 transitions to a diminished state, showing significantlyfewer display elements. Referring now to display 416 e, display element618 b is illuminated to show a central portion of the line. Displayelement 606, including the dust icon 606 a and appropriate dust levelindicators 606 b are illuminated. Display element 616, including theblower icon 616 a and appropriate blower speed indicators 616 b areilluminated. In this state, only the blower speed indicatorsrepresenting actual blower speed are illuminated blue. The availablehigher blower speeds are not illuminated. If any of the filters areexpired, the display will also show the filter life display elements600, 602, 604, including the ATS icon 605. In the example shown indisplay 416 f, the prefilter icon 600 is illuminated green to indicateit has remaining life, the particulate filter icon 602 and carbon filtericon 604 are illuminated red to indicate they are expired and the ATSicon is illuminated white.

An operator can place the ATS 410 in auto mode by touching the dustsensor icon 606 a. When the ATS 410 is in auto mode and a user isproximate, all of the display elements are illuminated as appropriate,as shown by display 416 g. Display elements 618 a-c are illuminated toshow the line. Display element 608 is illuminated to show the powericon. Display element 614 is illuminated white to show the night modeicon. Display element 606, including the dust icon 606 a and appropriatedust level indicators 606 b are illuminated. Because the ATS 410 is inauto mode, the dust icon 606 a is illuminated blue. Also, because thedust level is at the highest display level, all of the dust levelindicators 606 b are illuminated red. Display element 616, including theblower icon 616 a and appropriate blower speed indicators 616 b areilluminated. Because the ATS 410 is in auto mode, the blower icon 616 ais illuminated white. The blower speed indicators 616 b representingactual blower speed are illuminated blue. In this example, the blower isoperating at maximum speed so all indicators are illuminated blue.Display element 612 is illuminated white to indicate that the ATS 410 isnot in turbo mode. The filter life display elements 600, 602, 604,including the ATS icon, are illuminated. In this example, all of thefilters have remaining life and are therefore illuminated green. The ATSicon is illuminated white. Finally, the display element 620 isilluminated to display the WiFi icon. In this example, no WiFi transferis occurring so the WiFi icon is illuminated white. When the operator isno longer in proximity, the display 416 transitions to a diminishedstate, showing significantly fewer display elements. Referring now todisplay 416 h, display element 618 b is illuminated to show a centralportion of the line. Display element 606, including the dust icon 606 a(blue) and appropriate dust level indicators 606 b (red) areilluminated. Display element 616, including the blower icon 616 a(white) and appropriate blower speed indicators 616 b (blue) areilluminated. If any of the filters are expired, the display 416 willalso show the filter life display elements 600, 602, 604, including theATS icon 605 (See, for example, FIG. 416 f).

An operator can activate turbo mode by touching the turbo icon. When theATS 410 is in the turbo mode and a user is proximate, all of the displayelements are illuminated as appropriate, as shown by display 416 i.Display elements 618 a-c are illuminated to show the line. Displayelement 608 is illuminated white to show the power icon. Display element614 is illuminated white to show the night mode icon. Display element606, including the dust icon 606 a (white) and appropriate dust levelindicators 606 b are illuminated. Because the dust level is moderate,three dust level indicators are illuminated yellow. Display element 616,including the blower icon 616 a (white) and appropriate blower speedindicators 616 b are illuminated. Because the ATS 410 is in turbo mode,the blower is operating at maximum speed and all indicators 616 b areilluminated blue. Display element 612 is illuminated blue to indicatethat the ATS 410 is in turbo mode. The filter life display elements 600,602, 604, including the ATS icon 605, are illuminated. In this example,all of the filters have remaining life and are therefore illuminatedgreen. The ATS icon is illuminated white. Finally, the display element620 is illuminated to display the WiFi icon. In this example, no WiFitransfer is occurring so the WiFi icon is illuminated white. When theoperator is no longer in proximity, the display 416 transitions to adiminished state, showing significantly fewer display elements.Referring now to display 416 j, display elements 618 a and 618 b areilluminated to show the left and central portions of the line. Displayelement 606, including the dust icon 606 a (white) and appropriate dustlevel indicators 606 b (yellow) are illuminated. Display element 616,including the blower icon 616 a (white) and appropriate blower speedindicators 616 b (blue) are illuminated. Display element 612 isilluminated blue to indicate that the ATS 410 is in turbo mode. If anyof the filters are expired, the display 416 will also show the filterlife display elements 600, 602 and 604, including the ATS icon 605 (See,for example, display 416 f).

The ATS 410 can be placed in night mode by touching the night mode icon.When in night mode, the display 416 shows only the night icon 614illuminated red as illustrated in display 416 k. When in night mode, thecontrol system 412 limits the maximum speed of the blower 456 and slowsdown the rate at which the blower 456 transitions from one speed toanother. The control system 412 may be configured to implement otherfeatures when in the night mode. In this embodiment, the control system412 may operate in the manual or auto modes when in night mode. Forexample, the user may touch the night mode icon 614 while the controlsystem 412 is in either manual mode or auto mode, and the control system412 will transition to the night mode while otherwise continuing tooperate the blower 456 in accordance with the existing mode. Whentransitioning to night mode from manual mode, the control system 412will continue to operate the blower 456 at the manually specified speed,unless the manually set speed is above the maximum speed threshold. Ifso, the control system 412 reduces blower speed to match the maximumspeed threshold for night mode. When transitioning to night mode fromauto mode, the control system 412 allows the automatic speed controlalgorithms to control blower speed, except that the control system 412does not allow the blower speed to exceed the maximum speed thresholdand changes from one blower speed to another occur at a slowertransition rate.

The ATS 410 may also have the ability to connect to an externalapplication using WiFi or other wireless communications systems. Toenter wireless communication mode, the operator may touch the WiFi icon(display element 620). While the ATS 410 attempts to establish awireless connection, display element 620 may be illuminated blue in aflashing pattern, as shown by display 416 l. Once a connection inestablished and while the ATS 410 remains in wireless communicationmode, the flashing may terminate and the display element 620 may beilluminated blue, as shown by display 416 m. In this embodiment,wireless communications can be employed during any mode of operation andthe control system 412 may continue to operate the display 416 inaccordance with the existing mode of operation. Wireless communicationsmay be used to transfer relating to operation of the ATS 410 to a remotelocation, such as filter life data for the various filters, speed andtime of operation of the blower motor and dust sensor readings overtime. Wireless communications may also be used to send diagnosticinformation, including data that might allow individuals at a remotelocation to assess operation of the ATS 410 to determine whethermaintenance or repair is necessary. Further, wireless communications maybe used to update firmware and/or any other programming or datacontained within the control system 412.

The above description is that of current embodiments of the invention.Various alterations and changes can be made without departing from thespirit and broader aspects of the invention as defined in the appendedclaims, which are to be interpreted in accordance with the principles ofpatent law including the doctrine of equivalents. This disclosure ispresented for illustrative purposes and should not be interpreted as anexhaustive description of all embodiments of the invention or to limitthe scope of the claims to the specific elements illustrated ordescribed in connection with these embodiments. For example, and withoutlimitation, any individual element(s) of the described invention may bereplaced by alternative elements that provide substantially similarfunctionality or otherwise provide adequate operation. This includes,for example, presently known alternative elements, such as those thatmight be currently known to one skilled in the art, and alternativeelements that may be developed in the future, such as those that oneskilled in the art might, upon development, recognize as an alternative.Further, the disclosed embodiments include a plurality of features thatare described in concert and that might cooperatively provide acollection of benefits. The present invention is not limited to onlythose embodiments that include all of these features or that provide allof the stated benefits, except to the extent otherwise expressly setforth in the issued claims. Any reference to claim elements in thesingular, for example, using the articles “a,” “an,” “the” or “said,” isnot to be construed as limiting the element to the singular.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:
 1. An air treatment systemcomprising: a system housing having a front and a rear, said frontdefining an inlet, said rear defining an outlet; a plurality of filtersarranged in said filter housing; a blower for moving air through saidplurality of filters; a control system having a display and controllingoperation of said blower; a base affixed to a bottom of said systemhousing, said base having a plurality of fixed feet disposed toward saidrear of said system housing and a roller disposed toward the frontcenter of said filter housing; and a handle disposed toward a top ofsaid rear of said system housing, said handle including a central handleand a pair of side handles disposed on opposite sides of said centralhandle.
 2. The air treatment system of claim 1 wherein said base includea bobbin for manually wrapping said power cord, said bobbin disposedtoward said rear.
 3. The air treatment system of claim 2 wherein saidhandle is of a molded, one-piece construction.
 4. An air treatmentsystem comprising: a filter housing; a filter fitted into said housing,said filter having a frame and a clip rotatably mounted to said frame,said clip being manually movable between an open position and a closedposition, said clip configured to interact with said filter housing todraw said filter into said filter housing as said clip moves from saidopen position to said closed position and to secure said filter in saidfilter housing when in the closed position.
 5. The air treatment systemof claim 4 wherein said filter housing includes a locking protrusion andsaid clip includes a hook configured to engage said locking protrusionwhen in said closed position.
 6. The air treatment system of claim 5wherein said clip and said locking protrusion are configured such thatsaid hook enters into initial engagement with said locking protrusionpartially through movement between said open and closed positions andsuch that continued movement of said clip toward said closed positionfollowing said initial engagement draws said filter into said filterhousing.
 7. The air treatment system of claim 6 wherein said filterhousing include a shoulder and said filter includes a face seal engagedwith said shoulder, whereby drawing said filter into said filter housingcompresses said face seal against said shoulder.
 8. The air treatmentsystem of claim 7 wherein said hook and said locking protrusion areconfigured such that said hook is required to deform about said clip assaid clip is moved from said open position to said closed position, saiddeformation creating a snap-fit engagement resisting movement of saidclip into and out of said closed position.
 9. The air treatment systemof claim 7 wherein said filter includes a locking pin disposed adjacentsaid clip, said clip including an outer surface configured to interfitwith said locking pin when said clip is in said closed position creatinga snap-fit engagement resisting movement of said clip into and out ofsaid closed position.
 10. The air treatment system of claim 9 whereinsaid outer surface include a tooth, said tooth interacting with saidlocking pin to secure said clip is in said closed position.
 11. The airtreatment system of claim 9 wherein said outer surface defines a seat,said locking pin and said seat being interfitted when said clip is insaid closed position.
 12. The air treatment system of claim 11 whereinsaid outer surface includes a stop, said stop configured to engage withsaid locking pin to limit a range of motion of said clip.
 13. The airtreatment system of claim 4 wherein said clip is disposed toward one endof said filter; and wherein said filter includes a catch disposed towardan opposite end of said filter, said catch protruding from said frameand configured to engage with said filter housing, whereby said filteris secured in said filter housing fitting said catch into said filterhousing and moving said clip from said open position to said closedposition.
 14. The air treatment system of claim 4 wherein said filterinclude two clips arranged on opposite sides of said frame; and whereinsaid filter includes a catch protruding from said frame remote from saidclips.
 15. The air treatment system of claim 4 wherein said filterincludes one clip positioned near a top center of said filter.
 16. Afilter for an air treatment system comprising: a frame having a top, abottom and a pair of opposed sides; a filter media supported by saidframe; a catch protruding from said frame; and a retaining cliprotatably mounted to said frame, said clip being manually movablebetween an open position and a closed position, said clip beingconfigured to interact with a filter housing to draw the filter into thefilter housing and to secure the filter in the filter housing when inthe closed position.
 17. The filter of claim 16 wherein said catch isdisposed a said bottom of said frame and said clips are disposed towardsaid top of said frame.
 18. The filter of claim 17 wherein said clipincludes a hook configured to engage the filter housing when in saidclosed position.
 19. The filter of claim 18 wherein said hook isconfigured such that said hook is required to deform as said clip ismoved from said open position to said closed position, said deformationcreating a snap-fit engagement resisting movement of said clip into andout of said closed position.
 20. The filter of claim 18 furtherincluding a locking pin disposed adjacent said clip, said clip includingan outer surface configured to interact with said locking pin when saidclip is in said closed position creating a snap-fit engagement resistingmovement of said clip into and out of said closed position.
 21. Thefilter of claim 20 wherein said outer surface include a tooth and saidlocking pin defines a recess, said tooth and said recess beinginterfitted when said clip is in said closed position.
 22. The filter ofclaim 20 wherein said outer surface defines a seat, said locking pin andsaid seat being interfitted when said clip is in said closed position.23. The filter of claim 22 wherein said outer surface includes a stop,said stop configured to engage with said locking pin to limit a range ofmotion of said clip.